| Past: paleontological statistics software package for educaton and data anlysis Ø Hammer, DAT Harper Palaeontologia electronica 4 (1), 1, 2001 | 45644 | 2001 |
| PAST: Paleontological Statistics, Version 3.0 Ø Hammer, DAT Harper, PD Ryan Reference manual. Oslo: Natural History Museum University of Oslo, 2013 | 1082* | 2013 |
| The devonian period RT Becker, JEA Marshall, AC Da Silva, FP Agterberg, FM Gradstein, ... Geologic time scale 2020, 733-810, 2020 | 523 | 2020 |
| Harper, DAT, & Ryan, PD (2001). PAST: Paleontological statistics software package for education and data analysis Ø Hammer Palaeontologia electronica 4 (1), 9, 2009 | 476 | 2009 |
| The carboniferous period VI Davydov, DK Korn, MD Schmitz, FM Gradstein, Ø Hammer The geologic time scale 2012, 603-651, 2012 | 442 | 2012 |
| The ordovician period RA Cooper, PM Sadler, O Hammer, FM Gradstein The geologic time scale, 489-523, 2012 | 388 | 2012 |
| The silurian period MJ Melchin, PM Sadler, BD Cramer Geologic time scale 2020, 695-732, 2020 | 379 | 2020 |
| Rapid magma emplacement in the Karoo large igneous province H Svensen, F Corfu, S Polteau, Ø Hammer, S Planke Earth and Planetary Science Letters 325, 1-9, 2012 | 373 | 2012 |
| The permian period CM Henderson, SZ Shen, FM Gradstein, FP Agterberg Geologic time scale 2020, 875-902, 2020 | 257 | 2020 |
| Hydrocarbon seeps from close to the Jurassic–Cretaceous boundary, Svalbard Ø Hammer, HA Nakrem, CTS Little, K Hryniewicz, MR Sandy, JH Hurum, ... Palaeogeography, Palaeoclimatology, Palaeoecology 306 (1-2), 15-26, 2011 | 115 | 2011 |
| Developing a strategy for accurate definition of a geological boundary through radio-isotopic and biochronological dating: The Early–Middle Triassic boundary (South China) M Ovtcharova, N Goudemand, Ø Hammer, K Guodun, F Cordey, T Galfetti, ... Earth-Science Reviews 146, 65-76, 2015 | 102 | 2015 |
| Numerical simulation of upwelling currents in pockmarks, and data from the Inner Oslofjord, Norway Ø Hammer, KE Webb, D Depreiter Geo-Marine Letters 29, 269-275, 2009 | 88 | 2009 |
| High-resolution organic carbon–isotope stratigraphy of the Middle Jurassic–Lower Cretaceous Agardhfjellet Formation of central Spitsbergen, Svalbard MJ Koevoets, TB Abay, Ø Hammer, S Olaussen Palaeogeography, Palaeoclimatology, Palaeoecology 449, 266-274, 2016 | 85 | 2016 |
| PAST: Paleontological Statistics. Reference Manual Ø Hammer, DA Harper, PD Ryan Natural History Museum, University of Oslo. Oslo, Norway, 2015 | 84 | 2015 |
| Integrating subsurface and outcrop data of the Middle Jurassic to Lower Cretaceous Agardhfjellet Formation in central Spitsbergen MJ Koevoets, Ø Hammer, S Olaussen, K Senger, M Smelror Norsk Geologisk Tidsskrift 98 (4), 2018 | 82 | 2018 |
| Sculpting of rocks by reactive fluids B Jamtveit, Ø Hammer Geochemical Perspectives 1 (3), 341-342, 2012 | 81 | 2012 |
| PAST: paquete de programas de estadística paleontológica para enseñanza y análisis de datos Ø Hammer, D Harper, P Ryan Palaeontol. Electrón 4 (1), 4, 2001 | 72 | 2001 |
| A high-resolution Holocene record on the Southern Brazilian shelf: paleoenvironmental implications MM de Mahiques, IKC Wainer, L Burone, R Nagai, SHM e Sousa, ... Quaternary International 206 (1-2), 52-61, 2009 | 70 | 2009 |
| Biodiversity curves for the Ordovician of Baltoscandia Ø Hammer Lethaia 36 (4), 305-313, 2003 | 69 | 2003 |
| Astronomically forced cyclicity in the Upper Ordovician and U–Pb ages of interlayered tephra, Oslo Region, Norway HH Svensen, Ø Hammer, F Corfu Palaeogeography, Palaeoclimatology, Palaeoecology 418, 150-159, 2015 | 68 | 2015 |