Old children's book title required

[Chinajan]

I hope someone else might have read this, since all I can remember is the plot line. The book was set, and probably had been written, in the 1930s or 1940s. Enid Blyton style school mystery, involving a group of public school type girls and boys staying near a monastery during their summer holidays. Ghostly figures and robberies or spying are involved. The boys, of course, solve the mystery. In Scooby Doo style it is one of the monks who is the culprit. I think it was published by Blackie. Not Blyton, or any of the well known series like Jennings, Abbey Girls or Chalet School, as far as I can remember. Sorry to be so vague!

[woofgang]

go to abebooks.co.uk and try their booksleuth service