S. Ritzman

Hematology and immunology studies: the second manned Skylab mission.

P. Johnson, S. Kimzey, P C Johnson, 1976, Aviation, space, and environmental medicine.

Lymphocytes: morphological, developmental, and functional characteristics in health, disease, and experimental study--an analytical review.

W. C. Levin, S. Ritzman, J. C. Daniels, 1968, Texas reports on biology and medicine.