Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 47-60

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 121-128

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 255-257

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 275-335

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 61-106

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 41-46

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 35-38

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 23-32

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 259-270

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 249-254

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 177-185

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 139-146

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 195-197

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 205-229

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 39-40

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 187-194

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 337-339

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 113-120

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 399-402

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 357-363

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 365-378

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 393-397

Published in Transactions of the Royal Society of South Africa, in 1913, in volume 3, issue 1, pages 379-391