The Spring Full Moon

Alexander Thom , Megalithic sites in Britain (Oxford, 1967), chap. 9.

U.S. Naval Observatory, Interactive Computer Ephemeris.

Michael Hoskin Colleagues , “Studies in Iberian archaeoastronomy: (5) Orientations of megalithic tombs of northern and western Iberia”, Archaeoastronomy , no. 23 (1998), S39–87, Section M: “Central Alentejo region of Portugal”, by Hoskin Manuel Calado , pp. S77–82.

Michael Hoskin , Tombs, temples and their orientations: A new perspective on Mediterranean prehistory (Bognor Regis, 2001), 95–100.

Belmonte J. A. (ed.), Arqueoastronomia Hispana , 2nd edn (Madrid, 2000), chap. 3.