Professor Dickinson's commentary on the quotas involved in the Immigration Act of 1921 and of 1924. "Until the more recent enactment the meaning of nationality was obscured in a curious ambiguity ... the Act of 1921 made nationality the basis of the quote plan....
"Whether nationality was used in the scientific sense, however, meaning the character created by allegiance to a recognized nation or state, or whether its significance was arbitrary, referring only to such groupings as might be arranged by census makers or other such administrative officials, remained to be determined by judicial construction."
Professor Dickinson then narrates how this created an "intolerable situation" amended by the Immigration Act of 1924.
Dickinson, Edwin D. "The Meaning of Nationality in Recent Immigration Acts." Am. J. Int'l L. 19 (1925): 344–7.