“Study of local structure at crystalline rubrene grain boundaries via scanning transmission X-ray microscopy,” A.L. Foggiatto, Y. Takeichi, K. Ono, H. Suga, Y. Takahashi, M.A. Fusella, J.T. Dull, B.P. Rand, K. Kutsukake, T. Sakurai, Org. Electron., 74, 31