S.M. Bukasov. Potatoes of South America and their breeding use, Leningrad, 1933, p. 75.

Diagnosis: Stamen filaments are 2,5 mm long, anther 7 mm, column is oval, chinked, displaced, style is short, 10 mm, not overtopping the anthers. Berries are at first globular, ripe berries are oval, colored. Tuberisation is bad.
The position of this form among the others is unclear. It is distant in particular from v. bolivianum.
Juz. 1536, La Paz.