Semivalues of Simple Games

It is shown that each semivalue bounded semivalue on the class SG of monotonic simple games with a finite support can be uniquely extended to a semivalue continuous semivalue on the class G of all games with a finite support. We use this to show that the formula that is given for semivalues continuous semivalues on G by Dubey, Neyman and Weber also holds for semivalues bounded semivalues on SG. We also derive another formula for semivalues on SG in terms of the minimal winning coalitions of the game.