# Getting permission to reproduce an answer (with authorship credit) for a class handout/text

I have seen several answers that I would like to add to a set of handouts or a departmentally generated text. 1) How do I get permission, or is it granted automatically by the nature of this site? 2) How do I give credit, especially if the author uses a pseudonym? 2a) Is there a way to notify an author you would like to contact them offsite without giving others (the general population) your direct contact info?

• It might be polite to comment on the post you want to use and ask if the author is okay with this. For all you know, they might write something more tailored for your purposes. Win win, I say. – Jim Jul 23 '15 at 17:10
• @Jimself In fact, it is one of your answers that I want to use! physics.stackexchange.com/q/195550 – Bill N Jul 23 '15 at 17:23
• Awwwww. I'm touched. If it means even one more person stops thinking the Big Bang was an explosion in space, you can use it all you want. If you want to make mention, just give credit to Jim over on PSE. I don't need more than that. – Jim Jul 23 '15 at 17:36
• I'm feeling left out now ... – John Rennie Jul 23 '15 at 17:55
• @JohnRennie You have over 3000 answers. It takes time to go through them all. But having read some, I know I'd want a few of yours if I taught a related class. Besides, the law of large numbers says there's also probably an answer of yours where you made a mistake that actually happens to be correct and undiscovered physics. – Jim Jul 23 '15 at 18:00
• No, no, you can't sweet talk me now. I am inconsolable. I am going off to sit in a corner and eat chocolate. – John Rennie Jul 23 '15 at 18:03
• @JohnRennie I've copied your answer on Did the Big Bang happen at a point into the same handout. It's for them to have a full meal after Jim's appetizer! Can't decide who to add for dessert. Oh, and I added it before I read your comment. You just need to be more patient! – Bill N Jul 23 '15 at 18:27
• Whee! I feel better now! Of course, I have already eaten the chocolate :-) – John Rennie Jul 23 '15 at 18:28
• Looking for desserts? What's the overall subject of the handout? I'm sure John, Rob Jeffries, or I have an answer that addresses it – Jim Jul 23 '15 at 19:12
• The working title is Big Bang ideas. It's a handout for college students who won't be taking physics above intro level to counteract all the ideas about explosions in space (as you put it). Maybe a few answers about cosmological redshift and/or Hubble constant. Maybe even CMB uniformity vs anisotropy. – Bill N Jul 23 '15 at 19:20
• Definitely have a look through Rob Jeffries answers, they're a bit more technical than mine but I know they have what you need. I'll check and see if I have good ones. I'm not even going to attempt going through John's list. New ones are created faster than I can read the old ones – Jim Jul 23 '15 at 19:23
• Here is a thread that discusses how there is no center of mass in the universe. You might also use it or find a related one that discusses the lack of geometric center. physics.stackexchange.com/q/123875/23473 – Jim Jul 23 '15 at 19:28
• And John's are so LOONNGGG ... oops, I meant thorough ... uh, really good. I just hate it when I know the answer and John has already posted 3 paragraphs before I can get my 1 written. – Bill N Jul 23 '15 at 19:30
• He does write fast. The key is making yours easier to read while expressing the same amount, if not more, information. It's tricky, no doubt about that – Jim Jul 23 '15 at 19:32
• @BillN shameless self promotion, and imo the CC license is pretty clear on acceptable use :) – Kyle Oman Jul 24 '15 at 22:18

The license is set out in the "legal" link to be found in the footer of every page. It's a Creative Commons Attribution Share Alike license. I believe that the Creative Commons people feel that crediting a pseudonym covers the attribution requirement, and it is at least conceivable that a pseudonymous author may not want their real identity associated with the content.

You can attempt to contact individual authors on the site, or you can look in their profile for other contact information. You can assume that users who don't put contact info in their profiles probably don't want to be bothered. In my case you could work out my real contact info from a little digging, but I don't want to be pestered; so, please, only contact me directly for issues of import.

• For those who need or want it, the package ccicons has a variety of icons for Creative Commons licenses to use in LaTeX. – Bill N Jul 23 '15 at 17:47

The re-use of all the user-provided content on this site is permitted and encouraged. If you found the answers here helpful and you want to share them with your students, then by all means do so! We only ask that you attribute the content appropriately.

More technically, the legal conditions for reuse are spelled out on the footer of every page on the site:

The specific requirements of attribution are given in the second link. Specifically, and quoting from there, you must:

• Visually indicate that the content is from Stack Overflow or the Stack Exchange network in some way. It doesn't have to be obnoxious, a discreet text blurb is fine; and

• Show the author names for every question and answer.

In addition, if you publish this content online, you must:

• Hyperlink directly to the original question on the source site (e.g., http://stackoverflow.com/questions/12345); and

• Hyperlink each author name directly back to their user profile page on the source site (e.g., http://stackoverflow.com/users/12345/username).

Ideally you should include the URLs also in printed content. For more details see section 3 (Subscriber Content) of the Stack Exchange Terms of Service, which is available under legal on the footer of every page on the site.

There is an additional requirement from the CC BY-SA license, which is a bit fuzzier:

Attribution — You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work).

This means that if you remix the content or you edit parts of it, you must do so in a way which makes that evident and which enables your audience to find the author's original version.

Regarding pseudonyms, if a user's profile allows you to personally identify them, then it is indeed nice to provide both the name they publish under and their Stack Exchange pseudonym when giving credit. If the user has not provided their name, then it is perfectly OK to simply attribute the pseudonym: the user contributed the content in the understanding that it was available to all under CC BY-SA with attribution set to the pseudonym.

If you nevertheless want to attribute someone personally, it is OK to attempt to contact them as long as you don't do so too often. The first port of call is checking whether the user is available over at the h bar, our chatroom. If they are not, a short and polite comment under the answer you want to re-use is acceptable. As D. McKee mentioned, doing minor detective work to find the real-life identity of users is generally OK, but please use a good deal of caution and do not pester users off-site!

• On your last point: stress on minor detective work. A lot of people seem to get touchy about the kind of detective work that you or I would probably consider reasonable. – David Z Aug 4 '15 at 13:23