Though the rodent duo in this tale are named after the classic nursery rhyme "Hickory, Dickory, Dock"...
...the rhyme featured only a single, anonymous, mouse...and there's no one named "Dock" in the story!
Walt (Pogo) Kelly scripted and illustrated this story from Dell's Four Color Comics #220: Easter with Mother Goose (1949), which was the mouse duo's second (and last) appearance!
The first was several months earlier, in Dell's Four Color Comics #201: Christmas with Mother Goose (1948), where they assisted (as you might have guessed) Santa Claus!