David M. Valenzuela, Jennifer A. Griffiths, Jose Rojas, Thomas H. Aldrich, Pamela F. Jones, Hao Zhou, Joyce McClain, Neal G. Copeland, Debra J. Gilbert, Nancy A. Jenkins, Tammy Huang, Nick Papadopoulos, Peter C. Maisonpierre, Samuel Davis, George D. Yancopoulos
Proc Natl Acad Sci U S A. 1999 Mar 2; 96(5): 1904–1909. doi: 10.1073/pnas.96.5.1904