* Thommen GS: Biorhythms: is this your day? How you can chart your ups and downs for weeks, months, and even years ahead. Crown Ltd, 1st rev. Ed., New York, 1987 | * Thommen GS: Biorhythms: is this your day? How you can chart your ups and downs for weeks, months, and even years ahead. Crown Ltd, 1st rev. Ed., New York, 1987 |