I have a french etching with the triangle trademark SLL or SZL. The picture is of a person standing under 3 large trees with what looks like water in the background. I cannot read the signature. Looks like Honof? It is also signed in pencil and marked 73/350 in pencil. Etching is 19"X23". Framing looks original. Triangle trademark sticker is also on the back. Any ideas?