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Farmer, C.J. 2006. Strength In Numbers: Multiple Watchsites Improve Monitoring Efforts. Hawk Mountain News. Kempton, Pennsylvania.

Ruelas I., E. 2004. The RPI Project, 70 Years of Evolution. Hawk Migration Studies, Vol XXXI, No. 1.

Ruelas I., E. 2005. The Raptor Population Index Project: Current Status and Future Directions. Hawk Migration Studies, Vol XXXI, No. 2.

Ruelas I., E. 2005. The Raptor Population Index (RPI) Project In Its Second Year. Hawk Migration Studies, Vol XXXII, No. 1.

Ruelas I., E. 2006. The Case of the American Kestrel. Hawk Migration Studies, Vol XXXI, No. 2.

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Ruelas I., E. 2008. Continental-Scale Decline of the American Kestrel– North America’s Smallest Falcon. Raptor Watch, Vol. XXII, No. 3.

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