Mid Century charcoal drawing portrait. Help identify artist?

Hi there, I recently picked up this rather lovely drawing in a junk store. It is an original charcoal drawing and not a print. Looking at the style of hair and clothing I am assuming it is from the mid century? It is framed and glazed, the frame looks to have been painted white at some point.
The signature is quite difficult to read , therefore making identification and research very hard. Does anyone know this artist? I think the first word reads as Boris?! I've searched for artists with this name and can find nothing that resembles the surname... looks almost like a "la" or "lo" in the middle? It may well be an amateur artist who is not recorded, but the piece is extremely competent and well excecuted.
Any ideas or help would be very much appreciated.
Many thanks :)