Depending on the type of bingo, there is a designated set of balls with numbers written on them. 
https://mohr.no/pipermail/pressekontakter_mohr.no/2025-February/000016.html
https://roth-programmierung.de/pipermail/testliste_roth-programmierung.de/2024-November/000002.html
https://lists.uoregon.edu/pipermail/coe-test/Week-of-Mon-20240708/000027.html
https://lapizzateca.it/pipermail/prova_lapizzateca.it/2025-March/000000.html
https://tsahofheim.de/pipermail/paypal_tsahofheim.de/2024-December/000005.html
https://ujeph.edu.ht/pipermail/infirmieres_ujeph.edu.ht/2024-October/000012.html
http://ieisaacjpereira.edu.co/pipermail/usuarios_ieisaacjpereira.edu.co/2024-October/000003.html
https://kinderladen-os.de/pipermail/emailverteiler_kinderladen-os.de/2025-February/000364.html
https://helpcity.it/pipermail/esilvanio_helpcity.it/2025-March/000000.html
https://st-michael-flensburg.de/pipermail/kv_st-michael-flensburg.de/2024-November/000043.html
https://iifp.edu.au/pipermail/list_jasmine_iifp.edu.au/2025-March/000013.html
https://infoakte.de/pipermail/test_infoakte.de/2025-February/000010.html
https://fap.pt/pipermail/dirfap_fap.pt/2025-March/000001.html
https://pixelorchester.de/pipermail/team_pixelorchester.de/2025-February/000010.html
https://kassalauni.edu.sd/pipermail/deans_kassalauni.edu.sd/2024-October/000005.html
https://clairene.pl/pipermail/clrn_clairene.pl/2024-September/000004.html