Cita APA (7th ed.)

Einstein, C., & Westheim, P. Orbis Pictus. Ernst Wasmuth Verlag.

Cita Chicago (17th ed.)

Einstein, Carl, i Paul Westheim. Orbis Pictus. Berlin: Ernst Wasmuth Verlag.

Cita MLA (8th ed.)

Einstein, Carl, i Paul Westheim. Orbis Pictus. Ernst Wasmuth Verlag.