The Skylark Series

By E.E. "Doc" Smith.

The Skylark of Space was Doc Smith's first published work. That was back in 1928; although the book had been written in 1918. It took 10 years to sell, but when it did, it hit the field hard. It's widely cited as the first book to feature interstellar travel, and as having greatly expanded the playing field of the genre.

Smith's last book was also part of the Skylark series; the first part appeared in Worlds of If magazine in June of 1965.

The Skylark of Space

Skyark Three

The Skylark of Valeron

Skylark Duquesne