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Petrochelidon rufigula . Redthroated Cliff Swallow Hirondelle gorge fauve org page monograph of the Hirundinidae creator Richard Bowdler Sharpe PDold Petrochelidon rufigula Richard Bowdler Sharpe monograph of the Hirundinidae Petrochelidon rufigula Redthroated Cliff Swallow drawing June UTC Petrochelidon rufigula
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