Warttig SL, Forshaw MJ, South J, White AK. New, normative, English-sample data for the Short Form Perceived Stress Scale (PSS-4). J Health Psychol. 2013 Dec;18(12):1617-28. doi: 10.1177/1359105313508346
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.
Caso P, Sutherland GR, Fleming A, McDicken WN. Doppler tissue imaging: current status and future prospects. G Ital Cardiol. 1995 May 1;25(5):639-47.