@article{Jansen_1981, title={J.A. Brongers, Air photography and celtic field research in the Netherlands, 2 dln}, volume={96}, url={https://bmgn-lchr.nl/article/view/URN%3ANBN%3ANL%3AUI%3A10-1-102427}, DOI={10.18352/bmgn-lchr.2248}, number={2}, journal={BMGN - Low Countries Historical Review}, author={Jansen, H.P.H.}, year={1981}, month={Jan.}, pages={355–356} }