diff --git a/searx/engines/arxiv.py b/searx/engines/arxiv.py
index a1a58172..a4811ebd 100644
--- a/searx/engines/arxiv.py
+++ b/searx/engines/arxiv.py
@@ -3,9 +3,10 @@
  ArXiV (Scientific preprints)
 """
 
-from lxml import html
+from lxml import etree
+from lxml.etree import XPath
 from datetime import datetime
-from searx.utils import eval_xpath_list, eval_xpath_getindex
+from searx.utils import eval_xpath, eval_xpath_list, eval_xpath_getindex
 
 # about
 about = {
@@ -17,7 +18,7 @@ about = {
     "results": 'XML-RSS',
 }
 
-categories = ['science']
+categories = ['science', 'scientific publications']
 paging = True
 
 base_url = (
@@ -27,6 +28,23 @@ base_url = (
 # engine dependent config
 number_of_results = 10
 
+# xpaths
+arxiv_namespaces = {
+    "atom": "http://www.w3.org/2005/Atom",
+    "arxiv": "http://arxiv.org/schemas/atom",
+}
+xpath_entry = XPath('//atom:entry', namespaces=arxiv_namespaces)
+xpath_title = XPath('.//atom:title', namespaces=arxiv_namespaces)
+xpath_id = XPath('.//atom:id', namespaces=arxiv_namespaces)
+xpath_summary = XPath('.//atom:summary', namespaces=arxiv_namespaces)
+xpath_author_name = XPath('.//atom:author/atom:name', namespaces=arxiv_namespaces)
+xpath_doi = XPath('.//arxiv:doi', namespaces=arxiv_namespaces)
+xpath_pdf = XPath('.//atom:link[@title="pdf"]', namespaces=arxiv_namespaces)
+xpath_published = XPath('.//atom:published', namespaces=arxiv_namespaces)
+xpath_journal = XPath('.//arxiv:journal_ref', namespaces=arxiv_namespaces)
+xpath_category = XPath('.//atom:category/@term', namespaces=arxiv_namespaces)
+xpath_comment = XPath('./arxiv:comment', namespaces=arxiv_namespaces)
+
 
 def request(query, params):
     # basic search
@@ -41,30 +59,50 @@ def request(query, params):
 
 def response(resp):
     results = []
-
-    dom = html.fromstring(resp.content)
-
-    for entry in eval_xpath_list(dom, '//entry'):
-        title = eval_xpath_getindex(entry, './/title', 0).text
-
-        url = eval_xpath_getindex(entry, './/id', 0).text
-
-        content_string = '{doi_content}{abstract_content}'
-
-        abstract = eval_xpath_getindex(entry, './/summary', 0).text
-
-        #  If a doi is available, add it to the snipppet
-        doi_element = eval_xpath_getindex(entry, './/link[@title="doi"]', 0, default=None)
-        doi_content = doi_element.text if doi_element is not None else ''
-        content = content_string.format(doi_content=doi_content, abstract_content=abstract)
-
-        if len(content) > 300:
-            content = content[0:300] + "..."
-        # TODO: center snippet on query term
-
-        publishedDate = datetime.strptime(eval_xpath_getindex(entry, './/published', 0).text, '%Y-%m-%dT%H:%M:%SZ')
-
-        res_dict = {'url': url, 'title': title, 'publishedDate': publishedDate, 'content': content}
+    dom = etree.fromstring(resp.content)
+    for entry in eval_xpath_list(dom, xpath_entry):
+        title = eval_xpath_getindex(entry, xpath_title, 0).text
+
+        url = eval_xpath_getindex(entry, xpath_id, 0).text
+        abstract = eval_xpath_getindex(entry, xpath_summary, 0).text
+
+        authors = [author.text for author in eval_xpath_list(entry, xpath_author_name)]
+
+        #  doi
+        doi_element = eval_xpath_getindex(entry, xpath_doi, 0, default=None)
+        doi = None if doi_element is None else doi_element.text
+
+        # pdf
+        pdf_element = eval_xpath_getindex(entry, xpath_pdf, 0, default=None)
+        pdf_url = None if pdf_element is None else pdf_element.attrib.get('href')
+
+        # journal
+        journal_element = eval_xpath_getindex(entry, xpath_journal, 0, default=None)
+        journal = None if journal_element is None else journal_element.text
+
+        # tags
+        tag_elements = eval_xpath(entry, xpath_category)
+        tags = [str(tag) for tag in tag_elements]
+
+        # comments
+        comments_elements = eval_xpath_getindex(entry, xpath_comment, 0, default=None)
+        comments = None if comments_elements is None else comments_elements.text
+
+        publishedDate = datetime.strptime(eval_xpath_getindex(entry, xpath_published, 0).text, '%Y-%m-%dT%H:%M:%SZ')
+
+        res_dict = {
+            'template': 'paper.html',
+            'url': url,
+            'title': title,
+            'publishedDate': publishedDate,
+            'content': abstract,
+            'doi': doi,
+            'authors': authors,
+            'journal': journal,
+            'tags': tags,
+            'comments': comments,
+            'pdf_url': pdf_url,
+        }
 
         results.append(res_dict)
 
diff --git a/searx/engines/crossref.py b/searx/engines/crossref.py
new file mode 100644
index 00000000..d6131814
--- /dev/null
+++ b/searx/engines/crossref.py
@@ -0,0 +1,59 @@
+# SPDX-License-Identifier: AGPL-3.0-or-later
+# lint: pylint
+"""Semantic Scholar (Science)
+"""
+
+from urllib.parse import urlencode
+from searx.utils import html_to_text
+
+about = {
+    "website": 'https://www.crossref.org/',
+    "wikidata_id": 'Q5188229',
+    "official_api_documentation": 'https://github.com/CrossRef/rest-api-doc',
+    "use_official_api": False,
+    "require_api_key": False,
+    "results": 'JSON',
+}
+
+categories = ['science', 'scientific publications']
+paging = True
+search_url = 'https://api.crossref.org/works'
+
+
+def request(query, params):
+    params['url'] = search_url + '?' + urlencode(dict(query=query, offset=20 * (params['pageno'] - 1)))
+    return params
+
+
+def response(resp):
+    res = resp.json()
+    results = []
+    for record in res['message']['items']:
+        record_type = record['type']
+        if record_type == 'book-chapter':
+            title = record['container-title'][0]
+            if record['title'][0].lower().strip() != title.lower().strip():
+                title = title + ' (' + record['title'][0] + ')'
+            journal = None
+        else:
+            title = record['title'][0]
+            journal = record.get('container-title', [None])[0]
+        url = record.get('resource', {}).get('primary', {}).get('URL') or record['URL']
+        authors = [author.get('given', '') + ' ' + author.get('family', '') for author in record.get('author', [])]
+        isbn = record.get('isbn') or [i['value'] for i in record.get('isbn-type', [])]
+        results.append(
+            {
+                'template': 'paper.html',
+                'url': url,
+                'title': title,
+                'journal': journal,
+                'volume': record.get('volume'),
+                'type': record['type'],
+                'content': html_to_text(record.get('abstract', '')),
+                'publisher': record.get('publisher'),
+                'authors': authors,
+                'doi': record['DOI'],
+                'isbn': isbn,
+            }
+        )
+    return results
diff --git a/searx/engines/google_scholar.py b/searx/engines/google_scholar.py
index 41c62886..c07cd4ce 100644
--- a/searx/engines/google_scholar.py
+++ b/searx/engines/google_scholar.py
@@ -13,10 +13,12 @@ Definitions`_.
 
 from urllib.parse import urlencode
 from datetime import datetime
+from typing import Optional
 from lxml import html
 
 from searx.utils import (
     eval_xpath,
+    eval_xpath_getindex,
     eval_xpath_list,
     extract_text,
 )
@@ -46,7 +48,7 @@ about = {
 }
 
 # engine dependent config
-categories = ['science']
+categories = ['science', 'scientific publications']
 paging = True
 language_support = True
 use_locale_domain = True
@@ -99,7 +101,43 @@ def request(query, params):
     return params
 
 
-def response(resp):
+def parse_gs_a(text: Optional[str]):
+    """Parse the text written in green.
+
+    Possible formats:
+    * "{authors} - {journal}, {year} - {publisher}"
+    * "{authors} - {year} - {publisher}"
+    * "{authors} - {publisher}"
+    """
+    if text is None or text == "":
+        return None, None, None, None
+
+    s_text = text.split(' - ')
+    authors = s_text[0].split(', ')
+    publisher = s_text[-1]
+    if len(s_text) != 3:
+        return authors, None, publisher, None
+
+    # the format is "{authors} - {journal}, {year} - {publisher}" or "{authors} - {year} - {publisher}"
+    # get journal and year
+    journal_year = s_text[1].split(', ')
+    # journal is optional and may contains some coma
+    if len(journal_year) > 1:
+        journal = ', '.join(journal_year[0:-1])
+        if journal == '…':
+            journal = None
+    else:
+        journal = None
+    # year
+    year = journal_year[-1]
+    try:
+        publishedDate = datetime.strptime(year.strip(), '%Y')
+    except ValueError:
+        publishedDate = None
+    return authors, journal, publisher, publishedDate
+
+
+def response(resp):  # pylint: disable=too-many-locals
     """Get response from google's search request"""
     results = []
 
@@ -112,30 +150,53 @@ def response(resp):
     dom = html.fromstring(resp.text)
 
     # parse results
-    for result in eval_xpath_list(dom, '//div[@class="gs_ri"]'):
+    for result in eval_xpath_list(dom, '//div[@data-cid]'):
 
-        title = extract_text(eval_xpath(result, './h3[1]//a'))
+        title = extract_text(eval_xpath(result, './/h3[1]//a'))
 
         if not title:
             # this is a [ZITATION] block
             continue
 
-        url = eval_xpath(result, './h3[1]//a/@href')[0]
-        content = extract_text(eval_xpath(result, './div[@class="gs_rs"]')) or ''
-
-        pub_info = extract_text(eval_xpath(result, './div[@class="gs_a"]'))
-        if pub_info:
-            content += "[%s]" % pub_info
-
         pub_type = extract_text(eval_xpath(result, './/span[@class="gs_ct1"]'))
         if pub_type:
-            title = title + " " + pub_type
+            pub_type = pub_type[1:-1].lower()
+
+        url = eval_xpath_getindex(result, './/h3[1]//a/@href', 0)
+        content = extract_text(eval_xpath(result, './/div[@class="gs_rs"]'))
+        authors, journal, publisher, publishedDate = parse_gs_a(
+            extract_text(eval_xpath(result, './/div[@class="gs_a"]'))
+        )
+        if publisher in url:
+            publisher = None
+
+        # cited by
+        comments = extract_text(eval_xpath(result, './/div[@class="gs_fl"]/a[starts-with(@href,"/scholar?cites=")]'))
+
+        # link to the html or pdf document
+        html_url = None
+        pdf_url = None
+        doc_url = eval_xpath_getindex(result, './/div[@class="gs_or_ggsm"]/a/@href', 0, default=None)
+        doc_type = extract_text(eval_xpath(result, './/span[@class="gs_ctg2"]'))
+        if doc_type == "[PDF]":
+            pdf_url = doc_url
+        else:
+            html_url = doc_url
 
         results.append(
             {
+                'template': 'paper.html',
+                'type': pub_type,
                 'url': url,
                 'title': title,
+                'authors': authors,
+                'publisher': publisher,
+                'journal': journal,
+                'publishedDate': publishedDate,
                 'content': content,
+                'comments': comments,
+                'html_url': html_url,
+                'pdf_url': pdf_url,
             }
         )
 
diff --git a/searx/engines/pubmed.py b/searx/engines/pubmed.py
index 27444ae2..02e282d5 100644
--- a/searx/engines/pubmed.py
+++ b/searx/engines/pubmed.py
@@ -3,11 +3,15 @@
  PubMed (Scholar publications)
 """
 
-from flask_babel import gettext
 from lxml import etree
 from datetime import datetime
 from urllib.parse import urlencode
 from searx.network import get
+from searx.utils import (
+    eval_xpath_getindex,
+    eval_xpath_list,
+    extract_text,
+)
 
 # about
 about = {
@@ -22,7 +26,7 @@ about = {
     "results": 'XML',
 }
 
-categories = ['science']
+categories = ['science', 'scientific publications']
 
 base_url = (
     'https://eutils.ncbi.nlm.nih.gov/entrez/eutils/esearch.fcgi' + '?db=pubmed&{query}&retstart={offset}&retmax={hits}'
@@ -63,46 +67,61 @@ def response(resp):
 
     retrieve_url_encoded = pubmed_retrieve_api_url.format(**retrieve_notice_args)
 
-    search_results_xml = get(retrieve_url_encoded).content
-    search_results = etree.XML(search_results_xml).xpath('//PubmedArticleSet/PubmedArticle/MedlineCitation')
-
-    for entry in search_results:
-        title = entry.xpath('.//Article/ArticleTitle')[0].text
+    search_results_response = get(retrieve_url_encoded).content
+    search_results = etree.XML(search_results_response)
+    for entry in eval_xpath_list(search_results, '//PubmedArticle'):
+        medline = eval_xpath_getindex(entry, './MedlineCitation', 0)
 
-        pmid = entry.xpath('.//PMID')[0].text
+        title = eval_xpath_getindex(medline, './/Article/ArticleTitle', 0).text
+        pmid = eval_xpath_getindex(medline, './/PMID', 0).text
         url = pubmed_url + pmid
-
-        try:
-            content = entry.xpath('.//Abstract/AbstractText')[0].text
-        except:
-            content = gettext('No abstract is available for this publication.')
-
-        #  If a doi is available, add it to the snipppet
-        try:
-            doi = entry.xpath('.//ELocationID[@EIdType="doi"]')[0].text
-            content = 'DOI: {doi} Abstract: {content}'.format(doi=doi, content=content)
-        except:
-            pass
-
-        if len(content) > 300:
-            content = content[0:300] + "..."
-        # TODO: center snippet on query term
-
-        res_dict = {'url': url, 'title': title, 'content': content}
-
-        try:
-            publishedDate = datetime.strptime(
-                entry.xpath('.//DateCreated/Year')[0].text
-                + '-'
-                + entry.xpath('.//DateCreated/Month')[0].text
-                + '-'
-                + entry.xpath('.//DateCreated/Day')[0].text,
-                '%Y-%m-%d',
-            )
-            res_dict['publishedDate'] = publishedDate
-        except:
-            pass
+        content = extract_text(
+            eval_xpath_getindex(medline, './/Abstract/AbstractText//text()', 0, default=None), allow_none=True
+        )
+        doi = extract_text(
+            eval_xpath_getindex(medline, './/ELocationID[@EIdType="doi"]/text()', 0, default=None), allow_none=True
+        )
+        journal = extract_text(
+            eval_xpath_getindex(medline, './Article/Journal/Title/text()', 0, default=None), allow_none=True
+        )
+        issn = extract_text(
+            eval_xpath_getindex(medline, './Article/Journal/ISSN/text()', 0, default=None), allow_none=True
+        )
+        authors = []
+        for author in eval_xpath_list(medline, './Article/AuthorList/Author'):
+            f = eval_xpath_getindex(author, './ForeName', 0, default=None)
+            l = eval_xpath_getindex(author, './LastName', 0, default=None)
+            f = '' if f is None else f.text
+            l = '' if l is None else l.text
+            authors.append((f + ' ' + l).strip())
+
+        res_dict = {
+            'template': 'paper.html',
+            'url': url,
+            'title': title,
+            'content': content,
+            'journal': journal,
+            'issn': [issn],
+            'authors': authors,
+            'doi': doi,
+        }
+
+        accepted_date = eval_xpath_getindex(
+            entry, './PubmedData/History//PubMedPubDate[@PubStatus="accepted"]', 0, default=None
+        )
+        if accepted_date is not None:
+            year = eval_xpath_getindex(accepted_date, './Year', 0)
+            month = eval_xpath_getindex(accepted_date, './Month', 0)
+            day = eval_xpath_getindex(accepted_date, './Day', 0)
+            try:
+                publishedDate = datetime.strptime(
+                    year.text + '-' + month.text + '-' + day.text,
+                    '%Y-%m-%d',
+                )
+                res_dict['publishedDate'] = publishedDate
+            except Exception as e:
+                print(e)
 
         results.append(res_dict)
 
-        return results
+    return results
diff --git a/searx/engines/semantic_scholar.py b/searx/engines/semantic_scholar.py
index bda73104..b2701c33 100644
--- a/searx/engines/semantic_scholar.py
+++ b/searx/engines/semantic_scholar.py
@@ -6,6 +6,8 @@
 from json import dumps, loads
 from datetime import datetime
 
+from flask_babel import gettext
+
 about = {
     "website": 'https://www.semanticscholar.org/',
     "wikidata_id": 'Q22908627',
@@ -15,6 +17,7 @@ about = {
     "results": 'JSON',
 }
 
+categories = ['science', 'scientific publications']
 paging = True
 search_url = 'https://www.semanticscholar.org/api/1/search'
 paper_url = 'https://www.semanticscholar.org/paper'
@@ -47,9 +50,6 @@ def response(resp):
     results = []
 
     for result in res['results']:
-        item = {}
-        metadata = []
-
         url = result.get('primaryPaperLink', {}).get('url')
         if not url and result.get('links'):
             url = result.get('links')[0]
@@ -60,22 +60,47 @@ def response(resp):
         if not url:
             url = paper_url + '/%s' % result['id']
 
-        item['url'] = url
+        # publishedDate
+        if 'pubDate' in result:
+            publishedDate = datetime.strptime(result['pubDate'], "%Y-%m-%d")
+        else:
+            publishedDate = None
 
-        item['title'] = result['title']['text']
-        item['content'] = result['paperAbstract']['text']
+        # authors
+        authors = [author[0]['name'] for author in result.get('authors', [])]
 
-        metadata = result.get('fieldsOfStudy') or []
-        venue = result.get('venue', {}).get('text')
-        if venue:
-            metadata.append(venue)
-        if metadata:
-            item['metadata'] = ', '.join(metadata)
+        # pick for the first alternate link, but not from the crawler
+        pdf_url = None
+        for doc in result.get('alternatePaperLinks', []):
+            if doc['linkType'] != 'crawler':
+                pdf_url = doc['url']
+                break
 
-        pubDate = result.get('pubDate')
-        if pubDate:
-            item['publishedDate'] = datetime.strptime(pubDate, "%Y-%m-%d")
+        # comments
+        comments = None
+        if 'citationStats' in result:
+            comments = gettext(
+                '{numCitations} citations from the year {firstCitationVelocityYear} to {lastCitationVelocityYear}'
+            ).format(
+                numCitations=result['citationStats']['numCitations'],
+                firstCitationVelocityYear=result['citationStats']['firstCitationVelocityYear'],
+                lastCitationVelocityYear=result['citationStats']['lastCitationVelocityYear'],
+            )
 
-        results.append(item)
+        results.append(
+            {
+                'template': 'paper.html',
+                'url': url,
+                'title': result['title']['text'],
+                'content': result['paperAbstract']['text'],
+                'journal': result.get('venue', {}).get('text') or result.get('journal', {}).get('name'),
+                'doi': result.get('doiInfo', {}).get('doi'),
+                'tags': result.get('fieldsOfStudy'),
+                'authors': authors,
+                'pdf_url': pdf_url,
+                'publishedDate': publishedDate,
+                'comments': comments,
+            }
+        )
 
     return results
diff --git a/searx/engines/springer.py b/searx/engines/springer.py
index 512d71e5..2711fa80 100644
--- a/searx/engines/springer.py
+++ b/searx/engines/springer.py
@@ -19,7 +19,7 @@ about = {
     "results": 'JSON',
 }
 
-categories = ['science']
+categories = ['science', 'scientific publications']
 paging = True
 nb_per_page = 10
 api_key = 'unset'
@@ -41,32 +41,30 @@ def response(resp):
     json_data = loads(resp.text)
 
     for record in json_data['records']:
-        content = record['abstract'][0:500]
-        if len(record['abstract']) > len(content):
-            content += "..."
+        content = record['abstract']
         published = datetime.strptime(record['publicationDate'], '%Y-%m-%d')
-
-        metadata = [
-            record[x]
-            for x in [
-                'publicationName',
-                'identifier',
-                'contentType',
-            ]
-            if record.get(x) is not None
-        ]
-
-        metadata = ' / '.join(metadata)
-        if record.get('startingPage') and record.get('endingPage') is not None:
-            metadata += " (%(startingPage)s-%(endingPage)s)" % record
-
+        authors = [" ".join(author['creator'].split(', ')[::-1]) for author in record['creators']]
+        tags = record.get('genre')
+        if isinstance(tags, str):
+            tags = [tags]
         results.append(
             {
+                'template': 'paper.html',
                 'title': record['title'],
                 'url': record['url'][0]['value'].replace('http://', 'https://', 1),
+                'type': record.get('contentType'),
                 'content': content,
                 'publishedDate': published,
-                'metadata': metadata,
+                'authors': authors,
+                'doi': record.get('doi'),
+                'journal': record.get('publicationName'),
+                'start_page': record.get('start_page'),
+                'end_page': record.get('end_page'),
+                'tags': tags,
+                'issn': [record.get('issn')],
+                'isbn': [record.get('isbn')],
+                'volume': record.get('volume') or None,
+                'number': record.get('number') or None,
             }
         )
     return results
diff --git a/searx/searxng.msg b/searx/searxng.msg
index 3b876f96..c37240f8 100644
--- a/searx/searxng.msg
+++ b/searx/searxng.msg
@@ -43,6 +43,7 @@ CATEGORY_GROUPS = {
     'REPOS': 'repos',
     'SOFTWARE_WIKIS': 'software wikis',
     'WEB': 'web',
+    'SCIENTIFIC PUBLICATIONS': 'scientific publications',
 }
 
 STYLE_NAMES = {
diff --git a/searx/settings.yml b/searx/settings.yml
index 3f07bb2d..ba38e694 100644
--- a/searx/settings.yml
+++ b/searx/settings.yml
@@ -319,7 +319,6 @@ engines:
   - name: arxiv
     engine: arxiv
     shortcut: arx
-    categories: science
     timeout: 4.0
 
   # tmp suspended:  dh key too small
@@ -411,23 +410,9 @@ engines:
   #   api_key: 'unset'
 
   - name: crossref
-    engine: json_engine
-    paging: true
-    search_url: https://search.crossref.org/dois?q={query}&page={pageno}
-    url_query: doi
-    title_query: title
-    title_html_to_text: true
-    content_query: fullCitation
-    content_html_to_text: true
-    categories: science
+    engine: crossref
     shortcut: cr
-    about:
-      website: https://www.crossref.org/
-      wikidata_id: Q5188229
-      official_api_documentation: https://github.com/CrossRef/rest-api-doc
-      use_official_api: false
-      require_api_key: false
-      results: JSON
+    timeout: 10
 
   - name: yep
     engine: json_engine
@@ -1068,7 +1053,7 @@ engines:
     title_query: metadata/oaf:entity/oaf:result/title/$
     content_query: metadata/oaf:entity/oaf:result/description/$
     content_html_to_text: true
-    categories: science
+    categories: "science"
     shortcut: oad
     timeout: 5.0
     about:
@@ -1198,7 +1183,6 @@ engines:
   - name: pubmed
     engine: pubmed
     shortcut: pub
-    categories: science
     timeout: 3.0
 
   - name: pypi
@@ -1346,7 +1330,6 @@ engines:
     engine: semantic_scholar
     disabled: true
     shortcut: se
-    categories: science
 
   # Spotify needs API credentials
   # - name: spotify
@@ -1372,8 +1355,7 @@ engines:
   #   # working API key, for test & debug: "a69685087d07eca9f13db62f65b8f601"
   #   api_key: 'unset'
   #   shortcut: springer
-  #   categories: science
-  #   timeout: 6.0
+  #   timeout: 15.0
 
   - name: startpage
     engine: startpage