APA
Rugh Roberts, . (1951). The Frog. Tata Mcgraw-hill, New Delhi: .
Chicago
Rugh Roberts, . 1951. The Frog. Tata Mcgraw-hill, New Delhi: .
Harvard
Rugh Roberts, . (1951). The Frog. Tata Mcgraw-hill, New Delhi: .
MLA
Rugh Roberts, . The Frog. Tata Mcgraw-hill, New Delhi: . 1951.