Columbia subject headings:
Netherlands--Civilization.
Netherlands--Social conditions.
Woltjer, J. J. (Jan Juliaan), 1924---Bibliography.
Harvard subject headings:
Netherlands--Civilization.
Netherlands--Social conditions.
Woltjer, J. J. (Jan Juliaan), 1924---Bibliography.
Princeton subject headings:
Netherlands--History.
Woltjer, J. J. (Jan Juliaan), 1924-