Comparative spectrograms and corresponding oscillograms of different call types (A, Types 1 &amp; 2; B, Types 3, 4 and 5). Audio credit: (1, 2 &amp; 5) Robin K. Abraham and (3 &amp; 4) Ramprasad Rao.
Robin Kurian Abraham​, Jobin Kuruvilla Mathew, David Valiaparampil Raju, Ramprasad Rao, Anil Zachariah
CC BY-SA 4.0
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