The North America and Pelican nebula region, and the dark cloud that divides them, L935, in a DSS image. The black circle marks the position of the exciting source proposed by Comerón & Pasquali (2005). The asterisks mark the position of other five candidate O-type stars from Straižys & Laugalys (2008). The rectangle in the Gulf of Mexico region shows the area surveyed at Subaru telescope, corresponding to the field shown in Fig. 2. All coordinates are given in the equatorial J2000.0 system.