Deng is a pretty big family name with many clans. Does your father or grand father still know the name of their Hall (堂號)? Alternatively, if you know a fragmen

Deng is a pretty big family name with many clans. Does your father or grand father still know the name of their Hall (堂號)? Alternatively, if you know a fragment of the poem, you can DuckDuckGo it and see.