- E-bookThe Radio Boys on the Mexican BorderGerald Breckenridge
- E-bookThe Radio Boys Seek the Lost AtlantisGerald Breckenridge
- E-bookThe Radio Boys with the Revenue GuardsGerald Breckenridge
- E-bookThe Radio Boys Rescue the Lost Alaska ExpeditionGerald Breckenridge
- E-bookThe Radio Boys on Secret Service DutyGerald Breckenridge
- E-bookThe Radio Boys' Search for the Inca's TreasureGerald Breckenridge
- E-bookThe Radio Boys on Secret Service DutyGerald Breckenridge