| Title | A Photographic Periodogram of the Sun-Spot Numbers |
| Publication Type | Journal Article |
| Year of Publication | 1914 |
| Authors | Douglass, AE |
| Journal | The Astrophysical Journal, |
| Volume | XL |
| Issue | No. 3 |
| Keywords | Douglass, numbers, periodogram, photo, photographic, spot, sun, sun spot |
