These charts were prepared by me. They show the layouts for Wheatstone 30 and 40 button C/G anglo concertinas. These layouts were also used by Lachenal. The chart for Jeffries 30 button C/G follows. I shall add Jeffries 38 button layout as soon as I have prepared it.
Wheatstone 30 button C/G
Wheatstone 40 button C/G
Jeffries 30 button C/G