Microscopic view of rolling feldspars, Day Nui Con Voi, NW Vietnam. Deformed porphyroclasts rotate counter-clockwize as a result of ductile left-lateral shear along Ailao Shan - Red River shear zone.

Leloup et al. 1995, Tectonophysics
Leloup et al. 2001, J. Geophys. Res.