أرسل هذا في رسالة قصيرة: The compound equation related to the Bessel-Helmholtz equation and the Bessel-Klein-Gordon equation

  ______     ___      _____      ___              
 /_   _//   / _ \\   |__  //    / _ \\    ____    
 `-| |,-   | / \ ||    / //    / //\ \\  |    \\  
   | ||    | \_/ ||   / //__  |  ___  || | [] ||  
   |_||     \___//   /_____|| |_||  |_|| |  __//  
   `-`'     `---`    `-----`  `-`   `-`  |_|`-`   
                                         `-`