Cover of the original vinyl release
From Wikipedia:
Horizontal is the fourth studio album by the Bee Gees, and their second album to receive an international release. The LP was released in early 1968, and included the international hit singles “Massachusetts” and “World”.
Shown here is the US release on ATCO Records, featuring squished Sans Serifs Shaded and a classic LTypI with Max Miedinger’s Horizontal for the title. The original British release by Polydor had a cover with different type (Alfereta) and image.
See Bruce Eder’s review for Allmusic.
Cover of a later CD version