Cita APA (7a ed.)
Gray, P. Free to Learn: Why Unleashing the Instinct to Play Will Make Our Children Happier, More Self-Reliant, and Better Students for Life. Basic Books.
Cita estilo Chicago (17a ed.)
Gray, Peter. Free to Learn: Why Unleashing the Instinct to Play Will Make Our Children Happier, More Self-Reliant, and Better Students for Life. Nueva York, EUA: Basic Books.
Cita MLA (9a ed.)
Gray, Peter. Free to Learn: Why Unleashing the Instinct to Play Will Make Our Children Happier, More Self-Reliant, and Better Students for Life. Basic Books.
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