Autor: Hopcke, 21 de titluri

Hopcke,Robert,H

Thomas Hockenhull

Steve Hockensmith,Lisa Falco

Paul Hockenos

Steve Hockensmith,Science Bob Pflugfelder

Steve Hockensmith,Science Bob Pflugfelder

Jennifer Brown,Steve Hockensmith

Dennis Donovan,David Bock,Shirley O. Hockett

Shannon E. Perry,Marilyn J. Hockenberry,Deitra Leonard Lowdermilk,David Wilson,Kathryn Rhodes Alden,Mary Catherine Cashion