The Vanguard of Venus

From Author Wars - https://authorwars.com/publications/the-vanguard-of-venus-219517.html

Overview:

Title: The Vanguard of Venus
Author: Landell Barlett
Year: 1928
Publisher: Experimenter Publishing Company
Price: $0.00
Pages: 24
Binding: Pamphlet
Type: Chapter Book
Title Reference: The Vanguard of Venus
Notes: No price given. Cover says "Presented With the Compliments of Amazing Stories", suggesting that it was a giveaway.
Author's name is as "Landell Bartlett" on the story itself, but as "Landell Barlett" on the cover and title page. Everett F. Bleiler's "Science Fiction - The Early Years" states that it was "distributed as a subscription premium for Amazing Stories". However, the coupon in Amazing Stories, September 1928 (page 557) explains that it's "absolutely free to all readers" as a means of amassing circulation information on copies bought from newsdealers--although "if you are a subscriber we will not discriminate against you."