First Joiner's Problem/Historical Note

Historical Note on First Joiner's Problem

The First Joiner's Problem appears in the $1997$ work Mathematics and Chess by Miodrag S. Petković, where he credits it to E.I. Ignjat'ev, who published it in $1979$ in V Carstve Smekalki.

However, it appeared earlier than either in Boris A. Kordemsky's $1956$ collection Математическая смекалка, later translated into English and published in $1972$ as The Moscow Puzzles: 359 Mathematical Recreations, edited by Martin Gardner.