如何获取学术期刊（合法全文）

1. 图书馆副本

从图书馆目录、数据库的 "Full Text" / "Find It" 按钮，或 FindIt@Harvard 这类 Google Scholar 图书馆链接打开文章。不在校园时，用校园账号登录。

2. 合法开放副本

安装 Unpaywall 扩展，或把 DOI 粘贴进 Simple Query Tool。生物医学领域再查 PubMed Central 和 Europe PMC。NSF 资助的论文再查 NSF-PAR。存在多份合法副本时，优先 publishedVersion。

3. 馆际互借

通过图书馆的 ILL / 文献传递表格申请文章。写上 DOI。到货时间是本地政策，不是放之四海的 2–7 天。

4. 作者副本

给通讯作者发邮件，索取作者接受稿。这种请求是普通的学术惯例。把出版商 PDF 上传到社交网络不是同一回事。

It looks like the link you followed uses EZproxy and is no longer valid. Harvard Library has migrated its authentication from EZproxy to OpenAthens.

This error page will display until December 31, 2026.

Note that certain browser extensions, such as Zotero or Lean Library, may automatically add this proxy information to links.

• Harvard 的做法是用图书馆的 EZproxy 链接转换器改写旧书签，或在 HOLLIS 中检索题名。其他校园用新的代理主机或 OpenAthens 重定向器做同一件事。
• 从你自己的目录重新打开条目。不要在阅读清单里留一条失效的 ezproxy…/login?url= 链接。
• 若 Zotero 或 Lean Library 仍在链接前自动加上已停用的代理主机，先关掉扩展里的自动代理设置，再打开目录永久链接。

• 先打开出版商网站。 ScienceDirect 或 Wiley 显示付费墙，因为浏览器从未经过图书馆。在图书馆目录中检索题名，或点击 Institutional login。
• 失效的代理书签。 旧的 ezproxy…/login?url= 链接在图书馆改用 OpenAthens 或新代理主机后会失败。从目录重新打开条目。
• 访客或校友账号。 现场访问和校友权限比在读学生登录窄。向图书馆询问毕业后还剩什么；不要假定暑假或校友仍能访问。
• 是阅读器，不是 PDF。 有些平台流式播放阅读器，会话结束即消失。使用下载 / "Save PDF" 控件，并把 DOI 与文件放在一起。

click a library link, e.g., "FindIt@Harvard", to the right of the search result;

click a link labeled [PDF] to the right of the search result;

click "All versions" under the search result and check out the alternative sources;

click "Related articles" or "Cited by" under the search result to explore similar articles.

Online access to library subscriptions is usually restricted to patrons of that library. You may need to login with your library password, use a campus computer, or configure your browser to use a library proxy. Please visit your library's website or ask a local librarian for assistance.

Off-campus access links let you take your library subscriptions with you when you are at home or traveling.

The recorded subscription information expires after 30 days and is automatically deleted.

You can disable off-campus access links on the Scholar settings page.

若 30 天记录已过期，或你从未在校园检索过 Scholar，请用图书馆目录、VPN 或 Institutional login。不要把消失的 [PDF] 标签当成图书馆停订该刊的证据。

Yes! We harvest content from legal sources including repositories run by universities, governments, and scholarly societies, as well as open content hosted by publishers themselves.

Unpaywall finds the kind of articles you'd see in peer-reviewed scholarly journals like Science or PLOS One, plus pre-publication versions of similar work from preprint repositories like arXiv. Specifically, it looks for articles with a kind of identifier called a DOI.

Of the roughly 322 million works in OpenAlex, about 121 million (37%) are Open Access by this definition.

Host kind: publisher-hosted beats repository-hosted.

Version: publishedVersion beats acceptedVersion, which beats submittedVersion.

Direct PDF link: a location with a pdf_url beats one without.

Match quality (repository locations): a repository record matched to the work by DOI beats one matched by title.

Repository rankings: some major repositories, like PubMed Central and arXiv, rank above others.

Sites requiring registration. ResearchGate, a well-known academic social network, requires login before reading. OpenAlex already excludes it to stay on the right side of publishing agreements, but the registration wall would be a deal-breaker on its own.

Sites gated by CAPTCHAs. These make it hard for automated systems to verify that full text is really there, and make the links less useful — you never know whether a request will return the article or a puzzle. SSRN hosts many articles OpenAlex would love to include, but it prompts for CAPTCHAs and accounts after a few downloads.

你在 ResearchGate 见过的论文上出现绿色 Unpaywall 漏检，是预期现象。给作者发邮件索取接受稿，或走 ILL。不要把社交网络 PDF 当成已许可的开放副本。

Ioannidis JPA (2005) Why Most Published Research Findings Are False. PLoS Med 2(8): e124. https://doi.org/10.1371/journal.pmed.0020124

出版商 PDF

https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.0020124

PMC 记录

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1182327/

2022 年更正

https://doi.org/10.1371/journal.pmed.1004085

DOI 解析器

https://doi.org/10.1371/journal.pmed.0020124

题名

Attention Is All You Need

arXiv id

1706.03762

初版（Atom published）

2017-06-12T17:57:34Z

abs URL

https://arxiv.org/abs/1706.03762

PDF URL

https://arxiv.org/pdf/1706.03762

PubMed Central® (PMC) is a free full-text archive of biomedical and life sciences journal literature at the U.S. National Institutes of Health's National Library of Medicine (NIH/NLM).

PMC makes all content free to read (in some cases, following an embargo period), as NLM believes that the best way to ensure the accessibility and viability of digital material over time is through consistent and active use of the archive. However, free access does not mean that there is no copyright protection (see the PMC Copyright Notice).

The 2024 NIH Public Access Policy requires Author Accepted Manuscripts accepted for publication in a journal, on or after July 1, 2025, to be submitted to PubMed Central upon acceptance for publication, for public availability without embargo upon the Official Date of Publication.

Europe PMC provides comprehensive access to life sciences literature from trusted sources. It's available to anyone, anywhere for free.

When the full text is not available, Europe PMC can provide extended access to full text, with links to legal free copies via Unpaywall.

NSF maintains a publicly available repository of peer-reviewed publications: the NSF Public Access Repository.

NSF awardees must deposit all peer-reviewed publications and juried conference papers into the NSF Public Access Repository from awards resulting from proposals submitted, or due, on or after January 25, 2016.

Final versions of manuscripts accepted for publication after peer-review in either scholarly journals or juried conference papers or workshop proceedings (collectively referred to as author's accepted manuscripts or AAMs) must be deposited in NSF's Public Access Repository (PAR) at or before the time of publication.

Removing the 12-month publication embargo from all Portable Document Format (PDF) product types.

NIH 用期刊接受日期（2025 年 7 月 1 日）。NSF 用资助日期（2026 年 1 月 22 日）。2024 年 NSF 资助仍可能处在十二个月等待之后。仍然检索 NSF-PAR——接受稿可能已经公开。

By "open access" to this literature, we mean its free availability on the public internet, permitting any users to read, download, copy, distribute, print, search, or link to the full texts of these articles, crawl them for indexing, pass them as data to software, or use them for any other lawful purpose, without financial, legal, or technical barriers other than those inseparable from gaining access to the internet itself.

nothing in this clause prevents a library or archives from participating in interlibrary arrangements that do not have, as their purpose or effect, that the library or archives receiving such copies or phonorecords for distribution does so in such aggregate quantities as to substitute for a subscription to or purchase of such work.

We conclude that the CONTU Guidelines are outdated and should no longer be relied on as an appropriate measure of when ILL borrowing exceeds the statutory exemption in 17 U.S.C. § 108(g)(2).

The CONTU Guidelines are not, and never have been, enacted into law.

A borrowing library may receive copies of up to five articles from a single periodical title each year without paying any copyright fees. For each copy beyond that, a license fee (or a subscription) is required. This rule applies only to articles published within five years prior to the date of the ILL request. This is known as the "rule of five" or "suggestion of five."

• 文章题名、作者、期刊、年份、卷、期，以及你有的页码。
• DOI。完整的 10.… 标识符查找最快。见如何查找 DOI。
• 生物医学论文的 PMID 或 PMCID（当 PubMed 显示时）。NSF 资助论文的 PAR ID（当 NSF-PAR 显示时）。
• 你需要它的日期——真实截止日期，不是猜测。加急服务若存在，是本地选项，可能收费。
• 不要申请你已能通过目录、Unpaywall、PMC、Europe PMC 或 NSF-PAR 打开的文章。馆员会核验，你会白等一天。

主题：请求接受稿 — [article title]

尊敬的 [family name] 博士，我是 [institution] 的学生，正在做 [one-sentence topic]。我无法通过图书馆获取 "[article title]"（[journal]，[year]；DOI：[10.…]）。若您被允许分享作者接受稿，我将非常感谢得到一份供个人学习。感谢您的时间，[your name]。

Policy records contain information on how articles can be made open access for the published, accepted and submitted versions of an article.

The LibKey Nomad browser extension connects researchers who start on the open web at websites like PubMed, Wikipedia, and ChatGPT to Open Access and library-subscribed full text

• 先找合法开放副本。 Unpaywall、PMC、Europe PMC、NSF-PAR，以及 arXiv 这类学科仓储不要求校园凭据。
• 公共或州立图书馆。 许多公共图书馆许可较小的期刊集合，并运行自己的 ILL。带借书证，不要带出版商发票。
• 现场访问。 有些大学图书馆允许访客在馆内电脑上使用已许可数据库。开放时间和证件规则因地而异；出行前先打电话。
• 作者接受稿。 即使你没有在任何地方注册，上面的邮件模板仍然可用。
• 不要在第一屏就买 PDF。 在为公共图书馆也能申请的文件花个人钱之前，先核对本页四条路径。

Systematic downloading of batches of articles from the main PMC web site, in any way, is prohibited because of copyright restrictions.

Users of PMC are directly and solely responsible for compliance with copyright restrictions and are expected to adhere to the terms and conditions defined by the copyright holder.

• "Access denied" / "Purchase this article." 你在出版商网站上，没有 Institutional login。从图书馆目录打开同一 DOI，接上 VPN 或 OpenAthens 会话，或使用 Unpaywall。
• Scholar 上缺少图书馆链接。 设置最多五个图书馆，并存在 cookie 里。清除 cookie 后重新设置。解析器访问仍要求你是当前读者。
• 校外 Scholar 的 [PDF] 消失了。 30 天校外记录过期，或你从未在校园检索过。用目录或 VPN；不要假定订阅没了。
• Unpaywall 标签从不出现。 文章可能没有 DOI，或没有 Unpaywall 索引的合法 OA 副本。ResearchGate 和许多 SSRN 文件是故意漏检。那是真正的缺口，不是扩展坏了。去走 ILL 或给作者发邮件。
• PMC 记录是摘要或禁运页。 等到记录上显示的发布日，或申请 ILL / 接受稿。Europe PMC 仍可能露出 Unpaywall 副本。
• NSF 论文，PMC 是空的。 检索 NSF-PAR。NIH 与 NSF 不共用一个缴存柜。
• VPN 已连接，数据库空白。 在图书馆域名上关闭广告拦截，允许解析器使用的弹出窗口，并在假定期刊已停订之前查看图书馆状态页。
• Zotero 或 Lean Library 在前面加上失效代理。 Harvard 的停用页点名了这两个扩展。关掉自动代理设置，再打开目录永久链接。