1
Baskı/Yayın Bilgisi: 1937
Superior document: Annals of the astronomical observatory of Harvard College 88,6
2
Baskı/Yayın Bilgisi: 1933
Superior document: Annals of the astronomical observatory of Harvard College 88
3
Baskı/Yayın Bilgisi: 1923
Superior document: Studies of Class B stellar spectra containing emission lines [7]