• Helsinki University of Technology Inverse Problems group

• University of Helsinki, Rolf Nevanlinna Institute
  Lassi Päivärinta,
  Petri Ola,
  Mikko Kaasalainen,
  Simopekka Vänskä.

• University of Helsinki, Department of Mathematical Sciences
  Kari Astala.

• University of Jyväskylä
  Eero Saksman and his group.

• GE Healthcare/Instrumentarium Imaging
  Samuli Siltanen, see also his interview (in Finnish),
  Martti Kalke,
  Maaria Salo.

• Geological Survey of Finland
  Jukka Liukkonen.

• University of Kuopio
  Jari Kaipio,
  Ville Kolehmainen.

• Sodankylä Geophysical Observatory, University of Oulu
  Markku Lehtinen, his group and Inverse Ltd.

• Lappeenranta University of Technology
  Heikki Haario and his group.

Here are some of my collaborators around the world

• Michael Anderson, State University of New York, USA.
• Margaret Cheney, Rensselare Polytechnic Institute, USA.
• Allan Greenleaf, Rochester, USA.
• David Isaacson, Rensselaer, USA.
• Atsushi Katsuda, Okayama, Japan.
• Alexander Katchalov, Steklov Institute, Russia.
• Slava Kurylev, Loughborough, UK.
• Niculae Mandache, Loughborough, UK.
• Jennifer Mueller, Colorado State, USA.
• Vladimir Sharafutdinov, Novosibirsk, Russia.
• Michael E. Taylor, University of North Carolina, USA.
• Gunther Uhlmann, Washington, USA.
• Ricardo Weder, National Autonomous University of Mexico.

In Finland there are also various institutes solving inverse problems in practice.

• Instrumentarium Imaging, part of GE Healthcare Inc. is one of worlds biggest manufacturer of dental X-ray and mammography devices. The collaboration with Finnish inverse problems researcher and this company has been very active.

• The Finnish company Neuromag is specialized in noninvasively study the human brain by using electromagnetic measurements.

• The Finnish company Vaisala is famous on its weather radar systems.