2.
Magic Mud And Other Great Experiments/the Best of Dr. Zed's Brilliants Science Activities
by Penrose, Gordon, Holdcroft,...
ISBN: 9780920775189
List Price: $8.95
3.
Dr. Zed's Sensational Science Activities - Gordon Penrose - Paperback
by Penrose, Gordon, Holdcroft,...
ISBN: 9780920775530