Koenen, A. von.
1872.—Ueber die Organisation der Trilobiten. Verhandl. d. naturhist. Ver. d. preuss. Rheinl. u. Westphalen, vol. 29, C, pp. 93-95.
1880.—Ueber die Unterseite der Trilobiten. Neues Jahrb. f. Min.., Geol., u. Pal,, Bd. 1, pp. 430-432. pl. 8.
Lang, A.
1891.—Text-book of comparative anatomy, Eng. ed. (Bernard). London.
Lankester, E. R.
1881.—Observations and reflections on the appendages and on the nervous system of Apus cancriformis. Quart. Jour. Micros. Soc., vol. 21, pp. 343-376.
Laurie, M.
1911.—A reconstructed trilobite. Nature, vol. 88, p. 26.
Lindstroem, G.