Locations of the 72 galaxies that have velocity measurements: physical positions in supergalactic co-ordinates in the SGX-SGY-plane (left), SGX-SGZ-plane (centre), and SGY-SGZ-plane (right). Galaxies in the environment are marked as ‘field’ (grey pluses), galaxies for which M 81, M 82, NGC 3077, or NGC 2976 is the major disturber are summarised under ‘M 81 complex’ (black dots), the galaxy attributed to Holm II as its major disturber and Holm II itself are called the ‘HolmII system’ (red xs), and NGC 2403 and two satellites galaxies are called the ‘N2403 system’ (yellow squares). M 81, Holm II, and NGC 2403 are additionally highlighted by green stars. Larger symbols indicate galaxies that have Θ₁ < 0 and are thus unbound.