Eura, I'm not sure how these sources help you to better understand Blake's psychological state at the time he wrote the poem. You need to find out more about Blake. Also, if you are looking at these sources in terms of what others are saying about psychological themes in the poem, then that is a good way to use them. However, you want to make sure that you are using reliable sources, and I'm not sure about the reliability of these. Make sure that you apply the reliability test from the McGraw-Hill handbook before using these sources in your essay.