Behind the crystal ball
1996
Uncommon sense
2006
Empires of time
1989
People and the Sky
2008
Stairways to the stars
1997
Skywatchers of ancient Mexico
1980
Between the lines
2000
The Sky in Mayan literature
1992
Conversing with the planets
1992
Ancient astronomers
1993
Skywatchers
2001
The Book of the Year
2002
The Madrid Codex
2004
Book of the Year
2002
The Lines of Nazca
1990
The First Americans
2005
Foundations of New World Cultural Astronomy
2008
Archaeoastronomy in Pre-Columbian American
1975
Archaeoastronomy in the New World
1982
Das Rätsel von Nasca. Die gigantischen Bodenzeichnungen in der Wüste Perus
2001
The end of time
2009
