The question between A and B is, whether a certain deed is or is not forged, A affirms that it is genuine, B that it is forged.
1
A can prove a statement by himself that the deed is genuine, can B prove a statement by himself that the deed is forged.
2
A may prove a statement by B that the deed is genuine, and B may prove a statement by A that the deed is forged.
3
A may prove a statement by himself that deed is genuine.
4
A may prove the statement by himself that deed is forged.