Published in Proceedings of the Washington Academy of Science, in 1900, in volume 2, pages 161-184

Created: 2011-05-25, modified: 2011-06-21

Published in Proc. Wash. Acad. Sci., in 1900, in volume 2, pages 477-486

Created: 2010-01-11, modified: 2011-10-03

Published in Proc. Wash. Acad. Sci, in 1900, in volume 2, pages 541-604

Created: 2011-06-04, modified: 2011-06-21