Published in Journal of The Washington Academy of Sciences, in 1959, in volume 49, pages 19-26

Published in Journal of The Washington Academy of Sciences, in 1959, in volume 49, pages 27-32

Published in Journal of The Washington Academy of Sciences, in 1959, in volume 49, pages 54-61

Published in Jour Washington Acad Sci, in 1959, in volume 49, pages 106-112

Published in Journal of The Washington Academy of Sciences, in 1959, in volume 49, pages 117-120

Published in Jour Washington Acad Sci, in 1959, in volume 49, pages 122-128

Published in Journal of The Washington Academy of Sciences, in 1959, in volume 49, pages 157-163

Published in Journal of The Washington Academy of Sciences, in 1959, in volume 49, pages 178-182

Published in Jour Washington Acad Sci, in 1959, in volume 49, pages 183-187

Published in Journal of the Washington Academy of Sciences, in 1959, in volume 49, pages 188-192

Published in Jour Washington Acad Sci, in 1959, in volume 49, pages 193-195

Published in Jour Washington Acad Sci, in 1959, in volume 49, pages 273-283

Published in Jour Washington Acad Sci, in 1959, in volume 49, pages 284-289

Published in Journal of The Washington Academy of Sciences, in 1959, in volume 49, pages 290-292

Published in Journal of The Washington Academy of Sciences, in 1959, in volume 49, pages 299-316

Published in Journal of The Washington Academy of Sciences, in 1959, in volume 49, pages 317-323

Published in Journal of The Washington Academy of Sciences, in 1959, in volume 49, pages 324-330

Published in Journal of The Washington Academy of Sciences, in 1959, in volume 49, issue 2, pages 45-52