[925] Paulson and Somerville Hastings 1914.

[926] Crombie 1872.

[927] [See p. 35.]

[928] Dufrenoy 1918.

[929] Arnold 1874.

[930] Kupfer 1894.

[931] [See p. 236.]

[932] Malme 1895.

[933] Bitter 1899.

[934] Hofmann 1906.