Bell, S., Marzano, M., Cent, J., Kobierska, H., Podjed, D., Vandzinskaite, D., …Mursic, R. (2008). What Counts? Volunteers and their organisations in the recording and monitoring of biodiversity. Biodiversity and Conservation, 17(14), 3443-3454. https://doi.org/10.1007/s10531-008-9357-9