TY  - BOOK
AU  - De Morgan,Augustus,1806-1871
TI  - On the study and difficulties of mathematics
PY  - 2012///
PB  - Project Gutenberg
N1  - Project Gutenberg; Freely available; Electronic text
UR  - http://www.gutenberg.org/etext/39088
UR  - http://www.gutenberg.org/license
ER  -