Electronic reproduction. [S.l.] : HathiTrust Digital Library, 2010.
Master and use copy. Digital master created according to Benchmark for Faithful Digital Reproductions of Monographs and Serials, Version 1. Digital Library Federation, December 2002. http://purl.oclc.org/DLF/benchrepro0212
English and Spanish.
Description based on no. 47 (Dec. 1989); title from PDF cover (JSTOR, viewed July 22, 2011).