The first edition of Bicycling has the letters ABCDEF on page 120. Copyright © 1972 by Western Publishing Company, Inc. Published by Golden Press. Cover price is $1.50. The number on the spine is 24351. Listed as a Golden Guide on the cover and a Golden Handbook on the inside front cover.
Shown below the softcover is the large hardcover version of Bicycling. I have yet to find this cover variant in a softcover edition. No price listed. The number on the back cover is 64351-4. The letters CDEFG are on page 120. Contents are the same as the softcover. (not shown to scale)
Bicycling was published as a Leisure Library edition in 1974. Same cover as the hardcover. The size is 5 by 7 ½ inches. Cover price is $2.95. A first of this edition will have the letters ABCDE on page 120. As far as I can tell the contents are the same as the Golden Press editions.
Image #1 also exists in a large (5 ¼ by 7 ¾ inch) hardcover. The number on the back cover is 64351.
No revised edition exists. Out of print.