[325] Steiner 1881.

[326] Fünfstück 1899.

[327] Bachmann 1913.

[328] [See p. 215.]

[329] Friedrich 1906.

[330] Bachmann 1907.

[331] Bachmann 1904.

[332] Bachmann 1904.

[333] Stahlecker 1906.

[334] Lang 1903.