SMIT T, BAKHUIZEN T, GAASENBEEK CPH & MORAAL LG (1988) Occurrence of lead pellets around duck blinds and at clay pigeon grounds. LIMOSA 61 (3): 183-186.

The number of lead shot was determined around four duck blinds and at two clay pigeon grounds. Average numbers of lead shot varied from 14-2195 pellets per m2 (fig. I, tab. I)

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