1. Exotic terrane Publication/Creation: Oley, PA : Bullfrog Films, [2007?] Resource Type: Video or Visual Material Access & Availability: Loading
2. Exotic terrane Publication/Creation: [Oley, Pennsylvania] : [Distributed by] Bullfrog Films, [2016] Resource Type: Video or Visual Material Access & Availability: Loading
3. Expedition earthscope Publication/Creation: Oley, PA : Bullfrogfilms, [2006] Resource Type: Video or Visual Material Access & Availability: Loading
4. Expedition earthscope Publication/Creation: [Oley, Pennsylvania] : [Distributed by] Bullfrog Films, [2016] Resource Type: Video or Visual Material Access & Availability: Loading