# About the notation OSP(8|4) etc.

Are there any books or papers which explain these notations like OSP(N|4), sl(m|n)? It seems they are all considered as superalgebras, but how is this kind notation generally defined?
By the way, I know for a 3-d superconformal field theory, OSP(8|4) means a SO(8) R-symmetry and a Sp(4) conformal symmetry, which is isomorphic to SO(2, 3).
Thanks.