Franklin W. Dixon is the pen name used by the series of authors who have produced the various Hardy Boys books. The Hardy Boys, Nancy Drew, the Bobbsey Twins, and Tom Swift were all the creations of one Edward Stratemeyer, the founder of the Stratemeyer Syndicate. The most famous “Franklin” was Leslie McFarlane, a Canadian journalist who wrote 19 of the first 25 Hardy Boys books. (Writing as Carolyn Keene, McFarlane also contributed to the Dana Girls series.)
Note: McFarlane wrote several TV scripts for Bonanza.