O


O4If HD15570 HD190429A
O4V((f)) 9 Sgr
O4.5If HD14947
O4.5III(f) HD15558
O4.5V((f)) HD15629
O6.5I(n)fp λ Cep
O6.5V((f))z HD199579
O7Iafpvar UW CMa
O7Vzvar? HD54662
O7.5Iabf QZ Sge
O7.5IIIn((f)) ξ Per V1809 Cyg
O8Iape HD152408
O8fpe HD191612
O8Vn HD46056
O8II((f)) HD162978
O8.5II HD207198
O9Ia α Cam
O9II LY Aur
O9IIIvar ι Ori
O9V NU Ori
O9.2IV HD57682
O9.2IVnn ζ Oph
O9.5I V473 Per
O9.5Ia/ab V453 Sco
O9.5III X Per
O9.5IIInn HD93521
O9.5IVp θ2 Ori A
O9.5V σ Ori AE Aur
O9.5Vep GSC3973:812
O9.7Iabpvar V1357 Cyg
O9.7Ib V689 Mon
O9.7II HD10125
O9.7IIn V986 Oph
O9.7V υ Ori