Text this: Nonexistence of abelian difference sets: Lander's conjecture for prime power orders

 _    _      ___     __   __   __   __    _  _   
| \  / ||   / _ \\   \ \\/ //  \ \\/ //  | \| || 
|  \/  ||  / //\ \\   \   //    \ ` //   |  ' || 
| .  . || |  ___  ||  / . \\     | ||    | .  || 
|_|\/|_|| |_||  |_|| /_//\_\\    |_||    |_|\_|| 
`-`  `-`  `-`   `-`  `-`  --`    `-`'    `-` -`