I am using BiBTeX and would like to achieve the following: I am usually using a derivative of the alpha style, but for some entries I would like to define my own (preferred key). For example, I would like to reference EGAI as [EGAI] rather than [Gro60]. (If you don't know what EGA is, does not matter. The point is, that it is a book universally known in algebraic geometry as "EGA"). I tried various tricks such as defining the entry "key" without success. Perhaps complicating the question the fact that I would like to keep the rest of the keys as in alpha. An alternative solution I am willing to consider is a style where the original biblio entry would have to define the key to be used for everything, although this would be a last resort. Thanks for any help!
The shorthand key in biblatex works here, at least with the bibtex or bibtex8 backends. Haven't tried the natbib option linked above, and there's a very similar question at this link with a more complex answer that works with biber. MWE: