Adolf and Helmut Stern on vacation

This picture was taken in July 1921, during the holidays. Adolf Stern is on the right, on the left is his son Helmut Stern. The two women I cannot identify for sure, but next to Adolf is probably his wife Elizabeth Sternova, nee Willheim. My great-grandfather Adolf was born in 1871 in Humenne, then Austria-Hungary. He got married in 1902, to Elizabeth, who was born in 1873 and died in 1959 in Great Britain. She left Slovakia after the war. My grandfather was born in Opava in 1906, when my great-grandfather was working there. My grandfather attended the Czechoslovak State Trade Academy in Bratislava from 1922-23. At least two thirds of the students were of Jewish origin. The only person still alive from his class is Mr. Marcel Kucera, who is about 90 now. After the war my grandfather worked as an accountant.