Massive Charged Scalar Quasinormal Modes of Reissner-N\"ordstrom Black   Hole Surrounded by Quintessence
  We evaluate the complex frequencies of the normal modes for the massive charged scalar field perturbations around a Reissner-N\"ordstrom black hole surrounded by a static and spherically symmetric quintessence using third order WKB approximation approach. Due to the presence of quintessence, quasinormal frequencies damp more slowly. We studied the variation of quasinormal frequencies with charge of the black bole, mass and charge of perturbating scalar field and the quintessential state parameter. 
Nijo Varghese and V. C. Kuriakose