by Büchi, Ulrich and Büchi, Greti
Reference:
Büchi, Ulrich and Büchi, Greti, “Die Megalithe der Surselva Graubünden”, Desertina, 1984.
Bibtex Entry:
@book{Buechi1984, author = "Büchi, Ulrich and Büchi, Greti", title = {Die Megalithe der Surselva Graubünden}, year = "1984", publisher = "Desertina"}