1 2 “Creator Profile: The Creators of Pikachu”. NA website of Pokémon. The Pokémon Company International. Sugimori: “Bulbasaur, Charmander, and Squirtle were all designed by Ms. Nishida.” ; Nishida: “I created the designs for Bulbasaur, Charmander, and Squirtle by working backward from their final forms. I wanted people to be surprised when it evolved into Charizard, so I designed the original Charmander in such a way that Charizard would be unimaginable.”
↑ “Creator Profile: The Creators of Pikachu”. NA website of Pokémon. The Pokémon Company International. Sugimori: “Bulbasaur, Charmander, and Squirtle were all designed by Ms. Nishida.” ; Nishida: “I created the designs for Bulbasaur, Charmander, and Squirtle by working backward from their final forms. I wanted people to be surprised when it evolved into Charizard, so I designed the original Charmander in such a way that Charizard would be unimaginable.”
↑ Pokédex: Shoots water at prey while in the water. Withdraws into its shell when in danger. Game Freak (19 tháng 10 năm 1999). Pokémon Yellow. Game Boy. Nintendo.
↑ Pokédex: It shelters itself in its shell, then strikes back with spouts of water at every opportunity. Game Freak (22 tháng 4 năm 2007). Pokémon Diamond and Pearl. Nintendo DS. Nintendo.
↑ Pokédex: Squirtle's shell is not merely used for protection. The shell's rounded shape and the grooves on its surface help minimize resistance in water, enabling this Pokémon to swim at high speeds. Game Freak (17 tháng 3 năm 2003). Pokémon Ruby and Sapphire. Game Boy Advance. Nintendo.
↑ Kusaka, Hidenori, & Mato. Pokémon Adventures: Legendary Pokémon, Vol. 2; Chapter 33, Chapter 15, "Wartortle Wars", (pg 7-20) VIZ Media LLC, December 6, 2001. ISBN1-56931-508-6.
