By Britannica
By Palmer, Alan, Veronica
By Odhams Press Limited
By Filimonova, Elena
By DK
By Oxford University Press
By Encyclopaedia Britannica
By Grolier
By Field Enterprises
By Delahunty, Andrew, Dignen, Sheila, Stock, Penny
By David Crystal
By collectif
By Rosalind Fergusson
By Harrap
By Field Enterprises Education Corporation
By Collins
By Seidl, Jennifer, McMordie, W.
By Hutchinson, Brian
By Awde
By Pearsall, Judy, Trumble, Bill
By Riquelme-Beneyto, Josephine
By McClung, L.Grant
By Robert P. Gwinn, et al
By N/A
By Unidentified Author