Biblio
“The Illusions Of Vision And The Canals Of Mars”. Popular Science Monthly. Popular Science Monthly.
. 1907. 
“Is Mars Inhabited?”. The Harvard Illustrated Magazine Vol. VIII (No. 6). The Harvard Illustrated Magazine.
. 1907. 
. 1899.
Douglass, AE_Mars_1899.pdf (6.24 MB)

“The Polar Cap Of Mars”. Astronomy And Astrophysics. Astronomy And Astrophysics.
. 1894. 