Bruce Tegner / Thor Publishing (1961)
Summary: This is another of Tegner's quasi-Aikido self-defense books, many of which are simply reincarnations of previous books. What sets this book apart is the fairly accurate description of the nature of Aikido as a benevolent, non-violent art, and the very early date of publication (1961), which means that it pre-dates practically all other English-language mainstream publications pertaining to Aikido, except for a Tomiki book from 1956, a couple by Makiyama in the late 50's or 1960, and Tohei's first book in 1960. Collectible for this reason, contents notwithstanding.
M.G. Harvey / Emerson Books (1967)
Summary: This is not strictly an Aikido book, but does have an Aikido component, along with Judo and Karate, and much information common to most Japanese arts, and known to aikidoka. It is a presentation of the practical aspects of these arts, and their use in real-world self-defense situations. First published in the UK in 1967, and later released in the US (1975) by Emerson Books.
Kenji Tomiki / Japan Travel Bureau (1956)
Summary: Renamed "Judo: With Aikido" in latest editions, this book is authored by Kenji Tomiki, one of the pillars of modern Judo and Aikido, and the founder of the Tomiki System of Aikido, which utilizes competition and scoring similar to competitive Judo. The book is a brief overview of dojo etiquette, and is well illustrated with technical photography. The Aikido "Appendix" comprises approximately forty percent of the overall volume, and is believed to be the earliest English-language Aikido work. Some early First Printings utilized an alternative (drawn vs. photo) dust jacket.