Analysis of information sources in references of the Wikipedia article "Chó sói bình nguyên Bắc Mỹ" in Vietnamese language version.
Great Plains wolf; buffalo wolf; loafer. This is another extinct subspecies. It once extended throughout the Great Plains from southern Manitoba and Saskatchewan southward to northern Texas.
Extinct Mammals of the United States: Plains wolf, Canus lupus nubilus (1926) — Great Plains
Extinct Mammals of the United States: Plains wolf, Canus lupus nubilus (1926) — Great Plains