These are some of the references I used. The rest are from those Stan provided for the assignment

Hey, Kevin Nice exercises. Overall they are well done, but there's a few things you can improve: Line weight - The division between the lateral and the posterior head is not clear cut in the majority of cases. A constant line and even divisions may lead to a boring and text book look Varying the weight of the line may improve the overall aspect and give a more natural look. Design - Overall I fell you're constantly designing the heads as inverted tear shapes. Also I feel that sometimes you're using the same curve in the biceps and triceps causing a bit of the snowman effect. Think about the flow other pose and if the muscles are contracting or stretching, vary the shapes and contrast your straights with curves. The arm has a real particular flow to it so be very mindful of that and how it can improve and balance your designs. Cross contours - Finally, Whenever you're doing this kind of study you don't need to always indicate the core shadow. In fact, always seek the most efficient way to represent the pose. When you have a leg or an arm going away or towards you it's easier to indicate it with cross contours to show the perspective than to indicate the core shadow. The first exercise suffers with this problems. It looks like you shortened the arm instead of showing that it's going away from us. Also, remember that you can use the border of the deltoids as a natural cross contour to show the cylindrical form of the arm. Best Regards

Hi @Jason Winter, great job! I think your drawing of assignment image 6 is especially succesful; you managed to show anatomical understanding in combination with cool shading very well! I'll do my best to help you further: - The multipennate structure of the lateral head is really tricky. You seem to understand it quite well, this shows especially in your drawing of assignment image 4. Though, in some places I can tell that you're struggling with it. One thing that could help is to practice doing roadmap like drawings, where you track and indicate where the fibers and tendons are going. Or you could do a tracing. Learning to draw the muscle from imagination could also be a good way to memorize and understand the structure thoroughly. - In side view drawings I don't think you're originating the posterior head in the right spot. One thing that could help is to lightly indicate the scapula, then control if the posterior head is attaching to the spine of scapula. - I attached a paintover regarding a tiny, tiny shading error, but I think you'll enjoy this since you really enjoy shading! Hope this helps :)

Hi @K.O. Light, really nice studies! - In the drawings on the top row, I think you're puting the humerus to close to the surface. It's closer to the center of the cylinder of the arm. A trick to help you place the bones accurately is to imagine touching the arm, feeling where the bone might be. I hope this was helpful :) Keep up the good work!

When I saw the thumbnail of the photo I got this hunch: "this is the best drawing I've seen Marco post". The gesture, the cleanliness, the overall composition is just really nice! I think you should dare to do more of these :)