The early English customs system :
a documentary study of the institutional and economic history of the customs from the thirteenth to the sixteenth century /
by Norman Scott Brien Gras ...

APA Citation

Gras, N. Scott Brien. (1918). The early English customs system: a documentary study of the institutional and economic history of the customs from the thirteenth to the sixteenth century. Cambridge: Harvard University Press; [etc., etc.].

MLA Citation

Gras, Norman Scott Brien, 1884-1956. The Early English Customs System: a Documentary Study of the Institutional And Economic History of the Customs From the Thirteenth to the Sixteenth Century. Cambridge: Harvard University Press; [etc., etc.], 1918.

Warning: These citations may not always be complete (especially for serials).