Paper by Washino et al. is accepted for publication in Journal of Colloid & Interface Science
"Normal viscous force of pendular liquid bridge between two relatively moving particles", Kimiaki Washino, Ei L. Chan, Taku Matsumoto, Seiji Hashino, Takuya Tsuji & Toshitsugu Tanaka, Journal of Colloid & Interface Science (in press)
http://dx.doi.org/10.1016/j.jcis.2017.01.088