1
2
प्रकाशित: 1951
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 38
3
प्रकाशित: 1937
Superior document: Annals of the Astronomical Observatory of Harvard College 89,10
4
5
प्रकाशित: 1959
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 158
6
प्रकाशित: 1945
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 273
7
प्रकाशित: 1945
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 274
8
प्रकाशित: 1934
Superior document: Annals of the Astronomical Observatory of Harvard College 89,4
9
प्रकाशित: 1950
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 35
10
प्रकाशित: 1946
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 282
11
प्रकाशित: 1953
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 47
12
प्रकाशित: 1960
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 161
13
प्रकाशित: 1954
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 67
14
प्रकाशित: 1957
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 108
15
प्रकाशित: 1956
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 80