# Are questions which ask for references to other questions, legal?

I was wondering if I could ask for references for a particular type of questions from MSE. Is it legal?

For example, if I wanted references of questions which were related to proving $$\lim_{n\rightarrow \infty} \frac{a^n}{n!}=0$$. (I had come across quite a lot of such types.)

There are many questions (a few of them [duplicate]s) that answer the question. But when we look at the answers to all those questions, we get to understand the different approaches to the same question. With every new answer to such type of question, we get to know something new. Sometimes these questions are not marked as duplicates due to slight change in the phrasing or different questions with exactly the same underlying concepts.

• Normally, you would be able to use Approach0, but the site is down until May 12. The tag [reference-request] exists but this is mostly used for references to books or journal articles since you could use Approach0. If your question isn't urgent, I would advise you to wait. – Toby Mak May 9 at 12:51
• Would you clarify what you by "reference of questions"? Do you mean simply links to such question? (The word reference might refer to something like the book where the problem/solution comes from, to mention just one possible meaning.) – Martin Sleziak May 9 at 12:51
• @TobyMak Until Approach0 is back, one might try SearchOnMath - and probably there are also some other similar search engines that I am not aware of. (Or one could try some other tricks which are useful when searching.) – Martin Sleziak May 9 at 12:54
• @Martin simply links. – Aatmaj May 9 at 13:10
• Maybe not all of them are among the duplicates. But in the case you listed as an example, one has to wonder whether the 20 answers and the 64 links which are offered among the linked-questions aren't already enough. – Martin Sleziak May 9 at 13:27
• @MartinSleziak. Thanks for mentioning SearchOnMath. But sometimes two questions with a similar concept have different names, hence search engines cannot comprehend. – Aatmaj May 10 at 6:17
• @MartinSleziak It was just an example I thought of. I just wanted to know whether such questions are legal. – Aatmaj May 10 at 6:18
• Re: have different names, hence search engines cannot comprehend. Maybe one possible strategy in such cases might be asking in the main chatroom or in the chatroom devoted specifically to searching. – Martin Sleziak May 10 at 6:28
• @MartinSleziak Thanks a lot! – Aatmaj May 10 at 6:30