Calling male of Pseudhymenochirus merlini.
Irisarri I, Vences M, San Mauro D, Glaw F, Zardoya R
CC BY 2.0
<cite style="font-style:normal">Irisarri I, Vences M, San Mauro D, Glaw F, Zardoya R. "<a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3111386">Reversal to air-driven sound production revealed by a molecular phylogeny of tongueless frogs, family Pipidae</a>". <i>BMC Evolutionary Biology</i>. <a href="https://en.wikipedia.org/wiki/Digital_object_identifier" class="extiw" title="w:Digital object identifier">DOI</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1186/1471-2148-11-114">10.1186/1471-2148-11-114</a>. <a href="https://en.wikipedia.org/wiki/PMID" class="extiw" title="w:PMID">PMID</a> <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pubmed/21524293">21524293</a>. <a href="https://en.wikipedia.org/wiki/PubMed_Central" class="extiw" title="w:PubMed Central">PMC</a>: <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3111386">3111386</a>.</cite>