User talk:IHunChan

Wikipedia and copyright
Hello IHunChan, and welcome to Wikipedia. Your additions to Fundamental theorems of welfare economics have been removed in whole or in part, as they appear to have added copyrighted content without evidence that the source material is in the public domain or has been released by its owner or legal agent under a suitably-free and compatible copyright license. (To request such a release, see Requesting copyright permission.) While we appreciate your contributions to Wikipedia, there are certain things you must keep in mind about using information from sources to avoid copyright and plagiarism issues.


 * You can only copy/translate a small amount of a source, and you must mark what you take as a direct quotation with double quotation marks (") and cite the source using an inline citation. You can read about this at Non-free content in the sections on "text". See also Help:Referencing for beginners, for how to cite sources here.
 * Aside from limited quotation, you must put all information in your own words and structure, in proper paraphrase. Following the source's words too closely can create copyright problems, so it is not permitted here; see Close paraphrasing. (There is a college-level introduction to paraphrase, with examples, hosted by the Online Writing Lab of Purdue.) Even when using your own words, you are still, however, asked to cite your sources to verify the information and to demonstrate that the content is not original research.
 * Our primary policy on using copyrighted content is Copyrights. You may also want to review Copy-paste.
 * If you own the copyright to the source you want to copy or are a legally designated agent, you may be able to license that text so that we can publish it here. Understand, though, that unlike many other sites, where a person can license their content for use there and retain non-free ownership, that is not possible at Wikipedia. Rather, the release of content must be irrevocable, to the world, into the public domain (PD) or under a suitably-free and compatible copyright license. Such a release must be done in a verifiable manner, so that the authority of the person purporting to release the copyright is evidenced. See Donating copyrighted materials.
 * In very rare cases (that is, for sources that are PD or compatibly licensed) it may be possible to include greater portions of a source text. However, please seek help at Media copyright questions, the help desk or the Teahouse before adding such content to the article. 99.9% of sources may not be added in this way, so it is necessary to seek confirmation first. If you do confirm that a source is public domain or compatibly licensed, you will still need to provide full attribution; see Plagiarism for the steps you need to follow.
 * Also note that Wikipedia articles may not be copied or translated without attribution. If you want to copy or translate from another Wikipedia project or article, you must follow the copyright attribution steps in Translation. See also Copying within Wikipedia.

It's very important that contributors understand and follow these practices, as policy requires that people who persistently do not must be blocked from editing. If you have any questions about this, you are welcome to leave me a message on my talk page. Thank you. — Diannaa 🍁 (talk) 20:54, 23 April 2019 (UTC)