Popp, F., Schommers, W., & Durr, H. (2002). What is life?: Scientific approaches and philosophical positions. World Scientific.

Popp, Fritz-Albert, Wolfram Schommers, and Hans-Peter Durr. What Is Life?: Scientific Approaches and Philosophical Positions. River Edge, NJ: World Scientific, 2002.

Popp, Fritz-Albert, et al. What Is Life?: Scientific Approaches and Philosophical Positions. World Scientific, 2002.