This is because, such a distinction is prevalent in many other sounds, some of which are (a) nasals in Tamil (Shanmugam, 1972) and Malayalam (Shanmugam, 1972;Ladefoged and Maddieson, 1996), (b) laterals in Albanian (Ladefoged and Maddieson, 1996), and (c) stops in certain dialectal variations of Swahili (Hayward et al., 1989).
it is sensible to conclude that the two distinct groups L + and L − induced by our algorithm are true representatives of two important linguistic typologies.