Cover art
Christensen, Ole C., and Niels Søndergaard. 1. Maj Mysteriet. Carlsen Comics 1991.

Christensen, Ole C., and Niels Søndergaard. Dimensionsdetektiven
Series note: Graphic novels 1. Maj Mysteriet, Den Anden Præsident, and Det tredje øje.
Original in: Danish.

Christensen, Ole C., and Niels Søndergaard. 1. Maj Mysteriet
Title trans.: The May 1 Mystery
What if: Denmark had a communist revolution c. 1920.
Summary: A Danish scientist discovers travel between different worlds and invites some of his "doubles" to an informal congress, at which one is murdered.
Series note: First story of the Dimensionsdetektiven.
Published: Carlsen Comics 1991 (8756252862).
Original in: Danish.
Translation: Norwegian as 1. mai mysteriet, Carlsen 1992.
Translation: German as Der Rätselhafte 1. Mai, Carlsen 1992.

Christensen, Ole C., and Niels Søndergaard. Den Anden Præsident
Title trans.: The Second President
What if: Several European states entered the USA c. 1910, making it the United States of the Free World (USFW).
Summary: A coup d'etat is plotted against the president, traveling to his home state of Denmark to inaugurate the new, 125-meter statue of "The Great Mermaid" in Copenhagen.
Series note: Second story of the Dimensionsdetektiven.
Published: Carlsen Comics 1993 (8756260725).
Original in: Danish.
Translation: German as Der Falsche Präsident, Carlsen 1993.

Christensen, Ole C., and Niels Søndergaard. Det tredje øje
Title trans.: The Third Eye
Divergence: 1941 CE
What if: Germany did not invade the Soviet Union in 1941, and the Axis won a smaller-scale World War II.
Summary: The divided city of Copenhagen becomes a "Singapore with Berlin walls" as the Axis powers fall out. Tensions rise 50 years later as the city reunites with German-occupied Denmark.
Series note: Third story of the Dimensionsdetektiven.
Published: Carlsen Comics 2001 (8756262728).
Original in: Danish.