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Retrieved 10 June 2022. Kemp, A C (2001). "Family
Bucocerotidae (Hornbills)". In Josep, del Hoyo; Andrew, Elliott; Sargatal,
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- By". Pets on Mom.
Retrieved 8 July 2020. Kemp, A C (2001). "Family
Bucocerotidae (Hornbills)". In Josep, del Hoyo; Andrew, Elliott; Sargatal,
Jordi (eds...