Originally published in 1975 by Scholastic. It's nice to see the book was recently reissued in 2010 by Dragonfly Books.
This was Lucy Bate's first children's book, although she was also an accomplished playwright. She only wrote one other children's book in 1989. She died in 1993.
Diane deGroat is an award-winning illustrator of over 130 books. Little Rabbit was her first picture book and remains one of her favorites. She currently lives in Amherst, MA. She has a fun website here.