RXTE-ASM detects the start of a possible state transition in Cygnus X-1 - Rushton, A.; Dhawan, V.; Fender, R.; Garrett, M.; Maccarone, T.; Miller-Jones, James; Paragi, Z.; Pooley, G.; Spencer, R.; Tudose, V. (IAU Central Bureau for Astronomical Telegrams, 2010)