function extraMint(address tokenHolder) public onlyAuthorized {
    uint value = token.balanceOf(tokenHolder);
    if(value != 0) {
      uint targetValue = value.mul(increaseK);
      uint diffValue = targetValue.sub(value);
      token.mint(this, diffValue);
      token.transfer(tokenHolder, diffValue);
    }
    minted[tokenHolder] = true;
    mintedList.push(tokenHolder);
  }