Indicia title for this issue is "Lassie." Publication date inferred from code number. The code number is Lassie O.S. #282-506, which would indicate that this book was planned to be Four Color #282. There is also an excess of blank space in the indicia between the title "LASSIE" and "Published by Dell Publishing Co." into which the "No. 1" is dropped. That extra space was presumably to accomodate the larger Four Color issue number.
The bottom portion of the cover has three scenes painted by Morris Gollub who also did the interior illustrations for this issue (Richard Richmond)
Inside front cover
Writer credit suggested by Jerry Bails's Who's Who of American Comic Books 1928-1999 (www.bailsprojects.com).
The Who's Who also notes that Mo Gollub was penciler and inker of the Lassie feature in 1950, hence the art ID.
Inside back cover
Back cover