Website allowing one to look up mathematicians, publications, and number of references for each paper I have been to such a website about a year ago when deciding which PhD program/advisor I wanted. I can't remember the name of the website! You could search someone's name and university etc. and it would pull up their publications, which journal they were in, and number of references that paper had in other papers. 

I used it specifically for mathematics, although it could have been a more general data base (I can't remember).
Maybe it was Zentralblatt (math-specific, partially free)?

Other possibilities (gathered from the comments to compile an answer) are Google Scholar, as well as Mathscinet (math-specific, non-free), Scopus (non-free), Web of Science (non-free).