00549cam a22002051 4500 1222143 BD-DhUL 20160110120212.0 730102s1960 maua 000 0 eng 60013294 BD-DhUL BD-DhUL BD-DhUL 520 SHS Source book in astronomy 1900-1950 / Cambridge: Harvard University Press, 1960. xv, 423 p. : ill. , 23 cm. Includes index. Astronomy. Shapley, Harlow. ddc REF 44551 44551