http://catalogo.fi.uba.ar/cgi-bin/koha/opac-search.pl?q=ccl=au%3AHertig%2C%20Ricardo%20R.%20and%20su-to%3ARELATIVIDAD&format=rss2 3 0 50 ISBN http://catalogo.fi.uba.ar/cgi-bin/koha/opac-detail.pl?biblionumber=113 By Hertig, Ricardo R.. Buenos Aires : El Ateneo, 1970 . xv, 362 p. : , Indice alfabético de materias 24 cm..

]]> http://catalogo.fi.uba.ar/cgi-bin/koha/opac-detail.pl?biblionumber=113 ISBN http://catalogo.fi.uba.ar/cgi-bin/koha/opac-detail.pl?biblionumber=339 By Hertig, Ricardo R.. Buenos Aires : El Ateneo, 1978 . xvii, 419 p. : , Indice alfabético de materias al final de la obra 22 cm..

]]> http://catalogo.fi.uba.ar/cgi-bin/koha/opac-detail.pl?biblionumber=339 ISBN http://catalogo.fi.uba.ar/cgi-bin/koha/opac-detail.pl?biblionumber=8579 By Hertig, Ricardo R.. Buenos Aires : El Ateneo, 1976 . xvi, 396 p. : , Indice de capítulos | Indice alfabético 24 cm..

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