Published:
Three Towers in Tuscany 1963 reprinted 1970 and 1972 with different wrapper
The Purple Valley 1964 reprinted 1970 and 1973
Dark Danger 1965 reprinted 1976 with a different wrapper
White Fire 1966 reprinted 1976 with a different wrapper
Power of Three 1968 reprinted 1972
The Dagger and the Flame 1970 reprinted 1975
Marston Master Spy 1978
and
Come to London 1967