Studies: Life Drawing

Figure Drawing exercises from photographs. For the topmost picture, I cannot find a link at present. It was taken from a photographer nicknamed 'Photoport'. For the picture at the bottom, here is a link to the original: http://hapismile.deviantart.com/gallery/#/dpscef. The top pictures took me about an hour half while the bottom took me an hour. Hope I can speed up with my next attempt and be looser with the unimportant details.