Published in Bulletin de la Classe des Science, Academie Royale de Belgique, in 1883, in volume 5, pages 712-748

Created: 2015-02-16, modified: 2015-02-16

Published in Bulletins de l'Académie royale des sciences, des lettres et des beaux-arts de Belgique, in 1883, in volume 6, pages 27-33

Created: 2016-12-01, modified: 2016-12-01