The Illustrated Dictionary of Gardening. By George Nicholson, assisted by J. W. H. Trail and J. Garrett. Four volumes, London. Supplement to same. By George Nicholson et al. London: 1900.

Noisette, Man. Comp. Jard.

Manuel Complet du Jardinier. Par M. Louis Noisette. Paris: 1860.

Oberdieck, Deut. Obst. Sort.

Deutschlands beste Obst-Sorten. Von. F. G. C. Oberdieck. Leipzig: 1881.

Oregon Agric.

Oregon Agriculturist. Edited by W. E. Williamson. Portland: 1891 to date.

Parkinson, Par. Ter.

Paradisi in Sole. Paradisus Terrestris. By John Parkinson. London: 1629.