Published in Anales De La Sociedad Cientifica Argentina, in 1956, in volume 161, pages 7-30

Published in An Soc Cient Argentina, in 1956, in volume 161, issue 4/6, pages 41-52

Published in Anales De La Sociedad Cientifica Argentina, in 1956, in volume 162, pages 148-159

Published in Anales De La Sociedad Cientifica Argentina, in 1956, in volume 162, pages 160-164