- "The Searchers" (1960)
- "The Big Game" (1962)
- `The Battle of the Giants` (1964)
- `The Great Battle of the Apes` (1965)
- 'Landet som tiden glemte' (1966)
- "Folket som tiden glemte" (1967)
- "Out of Time's Abyss" (1968)
- Beyond Time's End (1969)
- "Castle Death" (1970)
- "King Cobra" (1971)
- "Den tapte verden" (1972)
- Plague City (1973)
- `The Return of Tarzan` (1974)
- "The Warlord of Mars" (1975)
- "Prinsessen av Mars" (1976)
- "John Carter and the Giant of Mars" (1977)
- "The Gods of Mars" (1978)
- `Thuvia, Maid of Mars` (1979)
- "Tarnsman of Gor" (1980)
- Assassin of Gor (1981)
- `Slave Girl of Gor` (1982)
- "Rogue of Gor" (1983)
- "Captive of Gor" (1984)
- "Raiders of Gor" (1985)
- "Fight for Gor" (1986)
- `Tribesmen of Gor` (1987)
- "Outlaw of Gor" (1988)
- `Savages of Gor` (1989)
- Hunter of Gor (1990)
- "Killer of Gor" (1991)
- `Destroyer of Gor` (1992)
- "Beast Master of Gor" (1993)
- `Slave Lord of Gor` (1994)
- `Valdor, erobreren av Gor` (1995)
- "Trollmannen King of Gor" (1996)
- `Caballus, hesteherren av Gor` (1997)
- `The Heirs of Gor` (1998)
- `Tarl Cabbot, Ruler of Gor` (1999)
- `Lord of the Barge` (2000)
- `Iskongen` (2001)
- "The Lost Legion" (2002)
- `The Iron Wolves of the North` (2003)
- `The Last of the Celts` (2004)
- `Løvens stolthet` (2005)
- `The Eagle's Flight` (2006)
- "Ulvens hevn" (2007)
- "The Bear's Fury" (2008)
- `The Dragon's Fire` (2009)
- `Slangens skygge` (2010)
- "Edderkoppnettet" (2011)
- `The Scorpion's Sting` (2012)
- `Tigerkloen` (2013)
- `The Shark's Teeth` (2014)
- "Krokodillens kjever" (2015)
- `Elefantens snabel` (2016)
- `The Hippo's Charge` (2017)
- `The Rhino's Horn` (2018)
- `The Buffalo's Stampede` (2019)
- `Løvens brøl` (2020)
Noveller:
- "The Death Mask" (1960)
- "Tempelet til terror" (1961)
- "The Eye of the Idol" (1962)
- "The Curse of the Mummy" (1963)
- "The Man-Eaters of Tsavo" (1964)
- "The Leopard of the Snows" (1965)
- "Den hvite døden" (1966)
- "The Ghost Tiger" (1967)
- "The Giant Squid" (1968)
- "Loch Ness-monsteret" (1969)
- "Den avskyelige snømannen" (1970)
- "The Thunderbird" (1971)
- "The Quetzalcoatl" (1972)
- "Den store slangen" (1973)
- "The Vampire Bat" (1974)
- "Varulven" (1975)
- "The Zombie" (1976)
- "Mumien" (1977)
- "The Ghost" (1978)
- "The Demon" (1979)
- "Heksen" (1980)
- "Trollmannen" (1981)
- "The Sorcerer" (1982)
- "The Necromancer" (1983)
- "The Warlock" (1984)
- "The Enchanter" (1985)
- "The Conjurer" (1986)
- "The Illusionist" (1987)
- "The Trickster" (1988)
- "The Jester" (1989)
- "The Fool" (1990)
- "The Knave" (1991)
- "Ridderen" (1992)
- "The Rook" (1993)
- "Biskopen" (1994)
- "Dronningen" (1995)
- "Kongen" (1996)
- "Keiseren" (1997)
- "Keiserinnen" (1998)
- "Paven" (1999)
- "Kardinalen" (2000)
- "Biskopen" (2001)
- "Presten" (2002)
- "The Deacon" (2003)
- "Munken" (2004)
- "Nonnen" (2005)
- "The Saint" (2006)
- "Synderen" (2007)
- "The Devil" (2008)
- "The Heretic" (2009)
- "The Apostate" (2010)
- "The Blasphemer" (2011)
- "Ateisten" (2012)
- "The Agnostic" (2013)
- "The Deist" (2014)
- "The Pantheist" (2015)
- "The Polytheist" (2016)
- "Monoteisten" (2017)
- "The Henotheist" (2018)
- "The Animist" (2019)
- "Shintoisten" (2020)