Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1916, in volume 68, pages 1

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1916, in volume 68, pages 2-43

Published in Proceedings of the Academy of Natural Sciences of Philadelphia, in 1916, in volume 68, pages 45-66

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1916, in volume 68, pages 67

Published in Proc. Acad. nat. Sci. Philad., in 1916, in volume 68, pages 68-84

Published in Proceedings of the Academy of Natural Sciences, Philadelphia, in 1916, in volume 68, pages 87-314

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1916, in volume 68, pages 360-375

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1916, in volume 68, pages 389-414

Published in Proceedings of the Academy of Natural Sciences of Philadelphia, in 1916, in volume 68, pages 486-549

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1916, in volume 68, pages 614-618