https://digitalcollections.sit.edu/cgi/viewcontent.cgi?referer=&httpsredir=1&article=1780&context=isp_collection

 

https://www.jstor.org/stable/pdf/j.ctt1rfsrr9.8.pdf?refreqid=excelsior%3A804dcdcce2bc4f4da7f0150cfae530c0