Šedivé vlasy profesor zobrazeno pěst na studenty - Stock fotografie a obrázky

Senior lecturer showing idea gesture

Thoughtful senior lecturer sitting at table with pencil and notebook

Grey hair professor talking by smartphone and looking away

Smiling grey hair professor holding paper plane in lecture hall

Senior lecturer writing something on blackboard and showing one finger up

Grey hair professor using laptop at table in lecture hall

Senior lecturer holding book and pointing on something

Senior lecturer holding book and looking away

Serious senior man writing in notebook with pencil

Pensive handsome grey hair man thinking and looking at chessboard at home

Close-up shot of senior writer at workplace taking book from stack

Cheerful businessman in glasses voting near brick wall

Handsome grey hair man reading book at home

Thoughtful senior man with pencil and sheet of paper

Senior man in tweed suit reading notes in notebook with magnifying glass

Senior writer in tweed suit and eyeglasses with letter near workplace

Thoughtful senior writer holding stack of books

Senior man with sheet of kraft paper looking away at workplace

Thoughtful senior writer sitting at workplace against white brick wall