She was a photographer, who was Picasso's mistress 1937 - 1943.
The style is all Picasso's own. You might compare it to a kind of Expressionism, but it is not the same thing.
She wasn't always weeping, in fact Picasso painted her many times, see "woman in hat" series
There are many paintings of Dora Maar, as she was Picasso's mistress. They were not all painted in the same place or year.
oil on canvas i think tht means oil pastels??? i dunoo but ths wat it says on wikipedia l0olz xx