The first fifteen volumes come in both hardcover and softcover editions. The hardcovers are indexed separately. Dimensions differ for some volumes. Cover price may vary depending on printing. For the most part, the first fifteen had the indicia title of "Love and Rockets Book:" with the cover title coming after that. Most printings indicate this but some may not. After the fifteenth volume, all subsequent books use only the cover title but some may have numbering in the indicia.