Professor Challenger is a 5-book series with 5 released primary works first released in 1900 with contributions by Arthur Conan Doyle.
#1 of 5 in Professor Challenger
1900 • 174 Readers • 224 pages • 3.8
#2 of 5 in Professor Challenger
1913 • 18 Readers • 120 pages • 3.3
#4 of 5 in Professor Challenger
1928 • 5 Readers • 64 pages • 2.5
#5 of 5 in Professor Challenger
1929 • 5 Readers • 48 pages • 4