On the germination, development, and fructification of the higher Cryptogamia : and on the fructification of the Coniferæ - Hofmeister, Wilhelm, 1824 -1877 (Published for the Ray Society, by Robert Hardwicke, 1862)

On the organization of the fossil plants of the coal-measures. Further observations on the organization of the fossil plants of the coal-measures - Williamson, William Crawford, 1816 -1895 (1894)

On the physics and physiology of protoplasmic streaming in plants - Ewart, Alfred J. (Alfred James), 1872 -1937 (Clarendon Press, 1903)

The Ontario natural science bulletin - Wellington Field Naturalists' Club. (Wellington Field Naturalists' Club, 1913)

Opuscula philolichenum (J. Lendemer, 2014)

Opuscula philolichenum (J. Lendemer, 2016)

Organographie der Pflanzen, insbesondere der Archegoniaten und Samenpflanzen - Goebel, K. (Karl), 1855 -1932 (G. Fischer, 1913)

Organographie der Pflanzen, insbesondere der Archegoniaten und Samenpflanzen - Goebel, K. (Karl), 1855 -1932 (G. Fischer, 1898)

Organographie der Pflanzen, insbesondere der Archegoniaten und Samenpflanzen - Goebel, K. (Karl), 1855 -1932 (G. Fischer, 1915)