Väsynyt harmaa tukka professori koskettaa silmiä liitutaulu - Kuvapankin valokuva ja kuva

Happy senior lecturer holding paper plane in hand

Grey hair professor pointing on something with wooden pointer

Happy senior lecturer with open arms standing near blackboard

Grey hair professor looking at students rising hands

Grey hair professor pointing on something with finger at blackboard

Grey hair professor correcting something at blackboard

Grey hair professor pointing on something with pencil on blackboard

Pensive grey hair professor standing at blackboard with piece of chalk

Elderly man in bow tie and blue jacket using smartphone isolated on grey

Elderly man in shirt and jacket using smartphone isolated on grey

Smiling senior man holding digital tablet with blank screen isolated on grey

Cropped view of senior man in stylish clothes holding eyeglasses and digital tablet isolated on dark grey

Cheerful retired man celebrating victory after playing chess with friend isolated on white

Cropped image of professor drawing with piece of chalk at blackboard

Positive senior man talking on smartphone and pointing with finger isolated on grey

Cropped shot of senior man with pencil and sheet of paper