Librería Samer Atenea
Kálamo Books
Librería Perelló (Valencia)
Librería Elías (Asturias)
Librería Kolima (Madrid)
Librería Proteo (Málaga)
Originally published in 1969, this book examines the factors which at different historical periods led people to use one language (Swahili) rather than another, or within a given period, to use a particular language in one set of circumstances.