It has always seemed to me that the Mathematical Community gives a high importance to the act of properly citing an author (Do not write Erdos! It's Erdős. Cauchy must be read as in French, not as in English...).

Hence, I thought that it might be useful to ask your opinion about how to cite correctly a foreign and/or complicated author name in the references.
It seems that Bibtex handles only standard English style names well, and requires many workarounds for foreign names (see [here][1]). So it is better not to count on it too much.

Feel free to point out any suggestion, or even the problems you have come across when citing authors.

I'll start a list:

- **First, Middle, Last - Names.** 
OK, I think there are no doubts, "John Horton Conway" should be cited as "J. H. Conway". Note the whitespaces after each period.

- ✔ **Spanish names:** See the very good answer of Leo Alonso.

- **Chinese names:** Here I am often in trouble. I read that Chinese write their surname first and then their given name, but I think that in papers they are usually swapped. Also I heard that many Chinese have the same surname.

**THE FREE LOOKUP ANSWERS**

- The user zeno pointed out that the tool MRLookUp http://www.ams.org/mrlookup is free an can be used to get the bibtex of any article tracked by the AMS.

- Federico Poloni also suggested MRef http://www.ams.org/mref.

**THE "LET'S JUST CLOSE" ANSWERS**

Some users voted to close this question for different reasons. I answered this question thinking that how to cite an author correctly is often a problem for mathematicians, so address it on MO could have been useful for many users. I can agreed to close this question, probably choosing zeno answer as the best, BUT before I would like to see more comments and opinions, especially about Asian names. 

**NOTES:**

1) Many answered: "just look on MathSciNet". Unfortunately, MathSciNet is not free for everyone, so I think this is a quite unsatisfactory method.

2) The question is not about the transliteration of names, you can assume that the author already have a name written in a reasonable set of characters extending the Latin. The question is about the abbreviation of names in references.  

  [1]: http://nwalsh.com/tex/texhelp/bibtx-23.html
  [2]: https://en.wikipedia.org/wiki/Spanish_naming_customs#Naming_system_in_Spain