What cameras can this lens fit?

Voigtlander color-skopar 20mm f3.5 sl aspherical

I know you can use it on nikon rangefinders/slrs. But what other cameras?

If it's designed for a Nikon rangefinder, it might (there's a slight difference in back-focus) fit a Kiev 2, 3, 4 or 5 or the Contax II/III series from which both are derived. It won't fit (nor can it be adapted for) any SLR or DSLR.

If it's Nikon SLR fit, it will also fit the Kiev 19/20 SLRs.

I echo Andrew. First you need to find out if it works on a Nikon SLR or on a rangefinder - that is the fundamental matter - it won't work on both types. The back-focus is totally different for SLRs than it is for rangefinders.