1
Cyhoeddwyd: 1956
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 100
2
Cyhoeddwyd: 1955
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 68
3
Cyhoeddwyd: 1956
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 87
4
Cyhoeddwyd: 1946
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 284
5
Cyhoeddwyd: 1939
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 175
6
Cyhoeddwyd: 1945
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 275
7
Cyhoeddwyd: 1939
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 180
8
Cyhoeddwyd: 1944
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 260
9
Cyhoeddwyd: 1936
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 122
10
Cyhoeddwyd: 1952
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 42
11
Cyhoeddwyd: 1957
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 110
12
Cyhoeddwyd: 1952
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 45
13
Cyhoeddwyd: 1954
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 66
14
15
Cyhoeddwyd: 1938
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 144
16
Cyhoeddwyd: 1945
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 273
17
Cyhoeddwyd: 1945
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 274
18
Cyhoeddwyd: 1956
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 99
19
Cyhoeddwyd: [2013]
Superior document: Title is part of eBook package: De Gruyter HUP e-dition: Complete eBook Package
Links: Cael y testun llawn; Cael y testun llawn; Cover
20
Cyhoeddwyd: 1956
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 86