(1983) razem z Gordonem R. Dicksonem
Time Patrol Strażnicy czasu (Guardians of Time, 1960) Time Patrolman (1983) The Year of the Ransom (1988) The Shield of Time (1990) The Time Patrol (1991)
History of Rustum Orbita bez końca (Orbit Unlimited, 1961) New America (1982)
Operation Otherworld Operation Chaos (1971) Operation Luna (1999)
The Last Viking The Golden Horn (1980) razem z The Road of the Sea Horse (1980) razem z Karen Anderson The Sign of the Raven (1980) razem z Karen Anderson
Maurai Maurai and Kith (1982) Orion Shall Rise (1983)
Harvest of Stars Harvest of Stars (1993) Gwiazdy są także ogniem (The Stars Are Also Fire, 1994) Harvest the Fire (1995) The Fleet of Stars (1997)
Liga Polezotechniczna (Nicholas van Rijn) Wojna skrzydlatych (The War of the Wing-Men, 1958) Trader to the Stars (1964) The Trouble Twisters (1966) Satan's World (1969) The Earth Book of Stormgate (1978) Mirkheim (1977) The People of the Wind (1973)
Imperium Ziemskie (Dominic Flandry) Ensign Flandry (1966) A Circus of Hells (1970) The Rebel Worlds (1969) The Day of Their Return (1973) Agent of the Terran Empire (1965) Flandry of Terra (1965) A Knight of Ghosts and Shadows (1974) A Stone in Heaven (1979) The Game of Empire (1985) The Long Night (1983) Let the Spacemen Beware (1963)