Sub-Doppler laser cooling of fermionic 40K atoms in three-dimensional gray optical molassesD. Rio Fernandes, F. Sievers, N. Kretzschmar, S. Wu, C. Salomon and F. ChevyEPL, 100 6 (2012) 63001DOI: https://doi.org/10.1209/0295-5075/100/63001