Three paintings by Claude Marks (British, exh. 1899-1915), all gouache on tinted card, comprising: Alpine river landscape, signed lower right, 20 x 14in. (50.75 x 35.5cm.); an Estuary landscape, signed lower left, 15 x 11in. (38 x 28cm.); and Birds in flight over a marshland at dusk, signed lower le