McKenna SP, Whalley D. Assessment of biotechnology drugs: what are the issues? Letter to the editor. Health Policy (New York). 1999 Nov;49(3):195-7. doi: 10.1016/S0168-8510(99)00055-X
Yang J, Eickbush TH. RNA-induced changes in the activity of the endonuclease encoded by the R2 retrotransposable element. Mol Cell Biol. 1998 Jun;18(6):3455-65.