"He had not converted Gia Long to Christianity, but had succeeded in making Prince
Canh a Catholic zealot, universally condemned for having told his mother to throw feces on Buddhist images" A History of Vietnam by Oscar Chapuis, p.179 [1]
A Vietnamese Royal Exile in Japan by My-Van Tran, Tran My-Van, p.15 [2]
A Vietnamese Royal Exile in Japan by My-Van Tran, Tran My-Van, p.15-16 [3]
"Prince Canh is said to have died from the measles at the age of twenty-one.
However, French missionaries reported that he had been poisoned." Colonialism by Philip Wolny, p.45 [5]
A Vietnamese Royal Exile in Japan by My-Van Tran, Tran My-Van My Duong p.22 [6]