Re:Belarus to create a regulatory environment for circulatio...
by valvar on Friday December 22, 2017 @10:11AM
(#15987953)
They might mean a swan that is black on one side but white on the other, i.e. gives the appearance of being an extremely rare or a very common event, while in fact being the opposite.
https://en.m.wikipedia.org/wiki/Black_swan_theory