The discovery by Green and Schwarz in 1984 that ten-dimensional superstring theory is anomaly-free and finite only if the Yang-Mills gauge group is SO(32) or E8 x E8 has made the phenomenological possibilities of superstrings evident. Ths has resulted in a sudden surge of interest in superstrings unification. Since this fast-developing field is new to almost all theoretical physicist, this collection of basic pre-1985 references should be very valuable. This two volumes contain over 1000 pages of reprints plus some introductory comments by J Schwarz.