J. E.  Collin, ?Die Ausbeute der deutschen Chaco-Expedition 1925/26. - Diptera. (Fortsetzung) XXIX. Pipunculidae?, Konowia, vol. 10, pp. 171-176, 1931.

J. E.  Collin, ?Platypezidae, Pipunculidae?, in Diptera of Patagonia and South Chile - Part 6, fascicle 2 Phoridae (supplement), Platypezidae, Pipunculidae, Sphaeroceridae (Borboridae), Ephydridae, vol. 6, London: Oxford University Press, 1931, pp. 49-61.

J. E.  Collin, ?The British species of the genus Verrallia (Diptera)?, The Entomologist's monthly Magazine, vol. 67, pp. 234-236, 1931.

G. F.  Knowlton and Janes, M. J., ?Notes on some beneficial Utah Diptera?, Rev. App. Ent. Ser. A, vol. 19, p. 629, 1931.

S.  Matsumura, 6000 illustrated Insects of Japan-Empire. Tokyo: Toukou Shoin, 1931, p. 497.

O.  Ringdahl, ?Insektfaunan inom Abisko Nationalpark. III. 6. Flugor - Diptera brachycera?, K. Svenska Vetenskapsakademiens Skrifter I Naturskyddsärenden, vol. 18, pp. 1-32, 1931.

F. X.  Williams, Handbook of the insects and other invertebrates of Hawaiian sugar cane fields. Honolulu, Hawaii: Experiment Station of the Hawaiian Sugar Planters' Association, 1931, p. 400.