[775] Zopf in Schenk 1890, p. 448.

[776] Knop 1872.

[777] Zopf 1907.

[778] Hamlet and Plowright 1877.

[779] Braconnot 1825.

[780] Zopf 1907.

[781] Errera 1893.

[782] Euler 1908, p. 7.

[783] Rosendahl 1907.

[784] Knop 1872.