Prinzinger, R.; Schafer T.; Schuchmann K.L. (March 1992). "Energy metabolism, respiratory quotient and breathing parameters in two convergent small bird species : the fork-tailed sunbird Aethopyga christinae (Nectariniidae) and the Chilean Hummingbird Sephanoides sephanoides (Trochilidae)". Journal of Thermal Biology. 17 (2): 71–79. Bibcode:1992JTBio..17...71P. doi:10.1016/0306-4565(92)90001-V.
Paton, D. C.; Collins, B. G. (1989). "Bills and tongues of nectar-feeding birds: A review of morphology, function and performance, with intercontinental comparisons". Australian Journal of Ecology. 14 (4): 473–506. doi:10.1111/j.1442-9993.1989.tb01457.x. ISSN1442-9993.
Siegfried, W. R.; Rebelo, A. G.; Prŷs-Jones, R. P.; Prys-Jones, R. P. (1985). "Stem Thickness of Erica Plants in Relation to Avian Pollination". Oikos. 45 (1): 153. Bibcode:1985Oikos..45..153S. doi:10.2307/3565234. JSTOR3565234.
Valente, Luis M.; Manning, John C.; Goldblatt, Peter; Vargas, Pablo (2012-07-01). "Did Pollination Shifts Drive Diversification in Southern African Gladiolus? Evaluating the Model of Pollinator-Driven Speciation". The American Naturalist. 180 (1): 83–98. doi:10.1086/666003. ISSN0003-0147. PMID22673653. S2CID5989519.
Prinzinger, R.; Schafer T.; Schuchmann K.L. (March 1992). "Energy metabolism, respiratory quotient and breathing parameters in two convergent small bird species : the fork-tailed sunbird Aethopyga christinae (Nectariniidae) and the Chilean Hummingbird Sephanoides sephanoides (Trochilidae)". Journal of Thermal Biology. 17 (2): 71–79. Bibcode:1992JTBio..17...71P. doi:10.1016/0306-4565(92)90001-V.
Siegfried, W. R.; Rebelo, A. G.; Prŷs-Jones, R. P.; Prys-Jones, R. P. (1985). "Stem Thickness of Erica Plants in Relation to Avian Pollination". Oikos. 45 (1): 153. Bibcode:1985Oikos..45..153S. doi:10.2307/3565234. JSTOR3565234.
Siegfried, W. R.; Rebelo, A. G.; Prŷs-Jones, R. P.; Prys-Jones, R. P. (1985). "Stem Thickness of Erica Plants in Relation to Avian Pollination". Oikos. 45 (1): 153. Bibcode:1985Oikos..45..153S. doi:10.2307/3565234. JSTOR3565234.
Valente, Luis M.; Manning, John C.; Goldblatt, Peter; Vargas, Pablo (2012-07-01). "Did Pollination Shifts Drive Diversification in Southern African Gladiolus? Evaluating the Model of Pollinator-Driven Speciation". The American Naturalist. 180 (1): 83–98. doi:10.1086/666003. ISSN0003-0147. PMID22673653. S2CID5989519.
Valente, Luis M.; Manning, John C.; Goldblatt, Peter; Vargas, Pablo (2012-07-01). "Did Pollination Shifts Drive Diversification in Southern African Gladiolus? Evaluating the Model of Pollinator-Driven Speciation". The American Naturalist. 180 (1): 83–98. doi:10.1086/666003. ISSN0003-0147. PMID22673653. S2CID5989519.
Paton, D. C.; Collins, B. G. (1989). "Bills and tongues of nectar-feeding birds: A review of morphology, function and performance, with intercontinental comparisons". Australian Journal of Ecology. 14 (4): 473–506. doi:10.1111/j.1442-9993.1989.tb01457.x. ISSN1442-9993.
Valente, Luis M.; Manning, John C.; Goldblatt, Peter; Vargas, Pablo (2012-07-01). "Did Pollination Shifts Drive Diversification in Southern African Gladiolus? Evaluating the Model of Pollinator-Driven Speciation". The American Naturalist. 180 (1): 83–98. doi:10.1086/666003. ISSN0003-0147. PMID22673653. S2CID5989519.