Text this: Communication : spin-boson model with diagonal and off-diagonal coupling to two independent baths : ground-state phase transition in the deep sub-Ohmic regime

__    __    ______    _  __     ___      ______  
\ \\ / //  /_   _//  | |/ //   / _ \\   /_____// 
 \ \/ //    -| ||-   | ' //   / //\ \\  `____ `  
  \  //     _| ||_   | . \\  |  ___  || /___//   
   \//     /_____//  |_|\_\\ |_||  |_|| `__ `    
    `      `-----`   `-` --` `-`   `-`  /_//     
                                        `-`