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Meyer, John R. (December 2006). "The Last Texas Grizzly". Texas Parks & Wildlife. Archived from the original on August 10, 2020. Retrieved October 12, 2020.
"Eastern Mole". Natural Science Research Laboratory. Texas Tech University. Archived from the original on October 19, 2020. Retrieved October 16, 2020.
"Killer Whale". Natural Science Research Laboratory. Texas Tech University. Archived from the original on October 18, 2020. Retrieved October 24, 2020.