5038 320 10 The Twins Help A Hadrosaur Cressida Cowell Primary Author mixed material Brown Watson Primary Author mixed material Ladybird Primary Author mixed material Cressida Cowell Primary Author mixed material The Twins Meet A Massospondylus Cressida Cowell Primary Author mixed material mixed material Wigwam Primary Author mixed material Sue DiCicco Primary Author mixed material mixed material The Twins Have A Picnic With A Spinosaurus Cressida Cowell Primary Author mixed material