[Szychowski K., Systematyka rodzaju Astrophytum, b.d.b]
An account of Astrophytum systematics from Konrad Szychowski's private materials archive, preserved in two versions. It presents historical genus treatments, comparisons of species, varieties, names and features, and discussion of crossing plants in collections. The version labelled “mod” corrects name spellings and supplements the subgenera section.
Copy in the supplied material