1. National Audubon Society (NAS) (2021, February 12). History of the Christmas Bird Count. Available online: https://www.audubon.org/conservation/history-christmas-bird-count#:~:text=Beginning%20on%20Christmas%20Day%201900,holidays%20rather%20than%20hunt%20them.
2. National Audubon Society (NAS) (2021, February 21). The First Christmas Bird Count: December 25, 1900. Available online: http://nas-national-prod.s3.amazonaws.com/documents/First_Christmas_Bird_Count_birdsplaces.pdf.
3. Citizen science as an ecological research tool: Challenges and benefits;Dickinson;Annu. Rev. Ecol. Evol. Syst.,2010
4. United States Geological Survey (USGS) (2022, November 08). BBS Overview 2017. Available online: https://prd-wret.s3-us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/atoms/files/BBS%20overview%202017.pdf.
5. The eBird enterprise: An integrated approach to development and application of citizen science;Sullivan;Biol. Conserv.,2014