In his article on “The Horse Concoction", Tim Krabbe mentions retrograde analysis questions that center around checkmate and involve 10 rooks, knights, and bishops. The 10 rooks problem is one that he shows. It can also be found here on CSE.
However, he does not show the problems with 10 bishops and 10 knights by Dane Henrik Juel and the Dutchman Guus Rol, although who made which is unclear. I suspect that is goes respectively though. My question is this: can these by found somewhere online? I would like to take a look at them, out of curiosity and so I can learn more about retrograde analysis.
This is the exact quote from the article that contains the aforementioned information. As far as I can tell, the problems revolve around checkmate, to reiterate:
In the last few years this old idea, where all the pawns of one or even both sides promote to one kind of piece, had been taken up again by the Dane Henrik Juel and the Dutchman Guus Rol - first with Bishops, then with Knights. And when Goldsteen saw Rol's latest version of an earlier composition by Juel, something unusual happened to him: he was jealous. He was just pissed off that he hadn't thought of Juel's and Rol's ten-knight problem (add ten black Knights to a given position so that White can mate in 1).