A very magic two sided Magic Square

This was a gift from a friend and unfortunately I do not know who created the effect. There is a magic square on the white side of the card which adds up to 45. It needs all five pieces of card to make it. On turning the card over, a magic square adding up to 15 can be made on the brown side of the card, leaving the small square left over. It is a clever way of combining magic squares with an ‘extra piece’ puzzle. I would be pleased to add the originator’s name if anyone can supply it.