1903

• Mortensen T., 1903. The Danish Ingolf-Expedition 1895–1896. Vol. 4, No. 2. Echinoidea, parts 1 & 2. Bianco Luno, Copenhagen.
• Mortensen T., 1903. Lissodiadema: nouveau genre de diadematides.
• Mortensen T., 1903. Echinoderms from East Greenland.
• Mortensen T., 1903. Chaetodiadema granulatum ng, n. sp., a new diadematid from the Gulf of Siam.

1910

• Mortensen T., 1910. Die Echinoiden der Deutschen Südpolar-Expedition 1901-1903. G. Reimer.
• Mortensen T., 1910. Report on the echinoderms collected by the Danmark-Expedition at north-east Greenland. Luno.
• Mortensen T., 1910. The Echinoidea of the Swedish South polar expedition. Lithographisches Institut des …

1928

• Mortensen T., 1928. A Monograph of the Echinoidea. I. Cidaroidea. C. A. Reitzel & Oxford University Press, Copenhagen & London 1-551.

1933

• Mortensen, O.T.J. 1933. Biological observations on ophiurids, with descriptions of two new genera and four new species. Papers from Dr. Th. Mortensen's Pacific Expedition 1914-16. LXIII. Videnskabelige Meddelelser fra den Naturhistoriske Forening i Kjøbenhavn. 93: 171-195. Reference page. 

• Mortensen, O.T.J. 1933. Echinoderms of South Africa (Asteroidea and Ophiuroidea). Papers from Dr. Th. Mortensen's Pacific Expedition 1914-16. LXV. Videnskabelige Meddelelser fra den Naturhistoriske Forening i Kjøbenhavn. 93: 215-400; pl. VIII-XIX PDF Reference page. 

• Mortensen, O.T.J. 1933. The echinoderms of St. Helena (Other than crinoids). Papers from Dr. Th. Mortensen's Pacific Expedition 1914-16. LXVI. Videnskabelige Meddelelser fra den Naturhistoriske Forening i Kjøbenhavn. 93: 401-473; pl. XX-XXII. PDF Reference page. 

1940

• Mortensen, O.T.J. 1940. Echinoderms from the Iranian Gulf. Asteroidea, Ophiuroidea, and Echinoidea. Danish Scientific Investigations in Iran. Part 2, 55-112, 14 figs, 2 pls. Reference page. 

• Mortensen, O.T.J. 1940. Report on the Echinoidea collected by the United States Fisheries steamer "Albatross" during the Philippine Expedition, 1907-1910. Part 2: the Echinothuriidae, Saleniidae, Arbaciidae, Aspidodiadematidae, Micropygidae, Diadematidae, Pedinidae, Temnopleuridae, Toxopneustidae and Echinometridae. Bulletin of the United States National Museum, 100. 14(1): 1-52. BHL Reference page. 

1963

• Mortensen T., 1963. Report on the Echinoidea Collected by the United States Fisheries Steamer" Albatross" During the Philippine Expedition, 1907-1910...