The 2 mm Kolibri (also known as the 2.7 mm Kolibri Car Pistol or 2.7x9 mm Kolibri) is the smallest commercially available centerfire cartridge, patented in 1910 and introduced in 1914 by Franz Pfannl, an Austrian watchmaker, with financial support from Georg Grabner.
The 2 mm Kolibri (also known as the 2.7 mm Kolibri Car Pistol or 2.7x9 mm Kolibri) is the smallest commercially available centerfire cartridge Barnes, Frank C. Cartridges of the World. DBI Books, 1976, p.146, patented in 1910 and introduced in 1914 by Franz Pfannl, an Austrian watchmaker, with financial support from Georg Grabner.