I met the first time Martyn Clark in Fort Collins last summer. USGS scientist Stacey Archfield organised a meeting for modellers (to which I was not invited :-( ), and Martyn was part of the crew.
I did not his work up to recently. and after our meeting, he came out with three Water Resources Research Papers, that I am listing here for subsequent readings.
Clark, M. P., Kavetski, D., & Fenicia, F. (2011). Pursuing the method of multiple working hypotheses for hydrological modeling. Water Resources Research, 47(9), n/a–n/a. doi:10.1029/2010WR009827
Pablo A. Mendoza, Martyn P. Clark, Michael Barlage, Balaji Rajagopalan, Luis Samaniego, Gab Abramowitz and Hoshin Gupta, Are we unnecessarily constraining the agility of complex process-based models? , Water Resources Research, Volume 51, Issue 1, pages 716–728, January 2015
Clark, M. P., B. Nijssen, J. Lundquist, D. Kavetski, D. E. Rupp, R. A. Woods, J. E. Freer, E. D. Gutmann, A. E. Wood, L. D. Brekke, J. A. Arnold, D. Gochis, R. Rasmussen. 2015. A unified approach for process-based hydrologic modeling: Part 1. Modeling concept, Water Resources Research, doi:10.1002/2015WR017198.
Clark, M. P., B. Nijssen, J. Lundquist, D. Kavetski, D. E. Rupp, R. A. Woods, E. D. Gutmann, A. W. Wood, D. Gochis, R. Rasmussen, D. Tarboton, V. Mahat, G. Flerschinger, D. Marks. 2015. A unified approach for process-based hydrologic modeling: Part 2. Model implementation and case studies, Water Resources Research, doi:10.1002/2015WR017200.
A late addition, the technical note regarding this SUMMA stuff.