coffee grounds and Nitrogen

Question

Once these are usually used, only Phosphorus is left. I am not a chemist, but references acknowledge can prove or verify statements. I do not see that here.

Answer 1

Coffee grounds do contain significant amounts of nitrogen:
http://web.extension.illinois.edu/dmp/palette/110109.html
http://compost.css.cornell.edu/chemistry.html
The nitrogen content of coffee grounds is supported by scientific research as well.