Published in Contributions in Science (Los Angeles), in 1990, in volume 416, pages 1-41
Published in Contributions In Science (Los Angeles), in 1990, in volume 417, pages 1-11
Published in Contributions In Science (Los Angeles), in 1990, in volume 418, pages 1-9
Published in Contributions In Science (Los Angeles), in 1990, in volume 419, pages 1-42
Published in Contributions in Science (Los Angeles), in 1990, in volume 420, pages 1-26
Published in Contributions In Science (Los Angeles), in 1990, in volume 421, pages 1-39
Published in Contributions In Science (Los Angeles), in 1990, in volume 422, pages 1-20