diffusion (1) Dynamics (1) Article (1) Aspect (1) Congresses (1) Congresses (1) Social movements (1) Grammar, Comparative and general--Article (1) Gifts (1) Expression (1) Dynamics (1) Diffusion (1) Civilization (1) Chronology (1) Article (1) Chronology (1) Chronology (1) diffusion (1)