Suburban and interurban bus companies listed in the Russell's Official National Motor Coach Guide, which was primarily a resource for intercity bus lines.
Hemet Bus Line (from Riverside to Hemet, until 1953)
Citrus Belt Lines - served Pomona, Chino, Ontario, Upland, Guasti, Cucamonga, Alta Loma.
Fontana Bus Line - served Riverside, Fontana, Colton, Bloomington, Kaiser, Steel Mill, Ontario, Pedley, Maratoma, Anza Village.