Published in Jornal de Sciencias Mathematicas, Physicas e Naturaes, in 1884, in volume 9, pages 85-87

Created: 2017-01-25, modified: 2017-01-25

Published in Jornal de Sciencias Mathematicas, Physicas e Naturaes, in 1884, in volume 10, pages 1-10

Created: 2017-01-25, modified: 2017-01-25