Emended description of Gardnerella vaginalis and description of Gardnerella leopoldii sp. nov., Gardnerella piotii sp. nov. and Gardnerella swidsinskii sp. nov., with delineation of 13 genomic species within the genus Gardnerella - Vaneechoutte, M; Guschin, A; Van Simaey, L (Int J Syst Evol Microbiol, 2019)