The writing-riddle is an international riddle type, attested across Europe and Asia. Its most basic form was defined by Antti Aarne as 'white field, black seeds', where the field is a page and the seeds are letters. However, this form admits of variations very diverse in length and degree of detail. For example, a version from Astrakhan translates as "the enclosure is white, the sheep are black", while one from the Don Kalmyks appears as "a black dog runs on white snow", and literary riddlers especially have produced long variations on the theme, often overlapping with riddles on pens and other writing equipment.