Die Drei Schwestern (Grimm in German)
Die Bücher der Chronika der drei Schwestern (Musäus)
The Navel of the Earth (Greek)
The Tree that Reached Up to the Sky (Hungary)
Rella and the Three Sisters (Michele Nichols's version).
Additional Sources
The Animal Husbands Blecher, Swedish Folktales and Legends
The Animal Sons-in-Law Bodker, European Folktales
The Fair Fiorita Crane, Italian Popular Tales
The Orgeus Soul Villa, 100 Armenian Tales
The Sun, the Moon, and the Raven Afanasyev, Russian Fairy Tales
The Three Animal Kings Basile, Pentamerone, Day 4
The Three Princes Dawkins, Modern Greek Folktales
The Boy Weavers Campbell, Cloudwalking Country
What Came of Picking Flowers Lang, Grey Fairy Book