Geomagnetic field variation as inferred from archaeomagnetism in Greece and palaeomagnetism in British lake sediments since 700 b.c. - Xanthakēs, Iōannēs N. 1904-1994; Lyritzēs, Iōannēs 1953- (Grapheion Dēmosieumatōn tēs Akadēmias Athēnōn, 1991)