I think Cheung Jan (1)
http://hkmdb.com/db/people/view.mhtml?i ... ay_set=eng
is an alias for Cheung Ching-Fung
http://hkmdb.com/db/people/view.mhtml?i ... ay_set=eng

I know that in four films (Black Bull and White Snake, Magnificent Chivalry, Fearless Fighters, and Iron Swallow), Cheung Jan is in the cast list and Cheung Ching-Fung (not credited) can be seen on screen.

Another bit of evidence is in the film Young Flying Hero. Cheung Ching-Fung is credited on the poster and on-screen credits, but the HKFA gives credit to Cheung Jan.

Does anyone have further evidence that Cheung Ching-Fung and Cheung Jan (1) are the same person, or contrary evidence that they could not be the same person. (Is Cheung Jan (1) credited for any films in which Cheung Ching-Fung cannot be seen?)

Cheung Ching-Fung is also in "Purple Darts" with only the name Cheung Jan in the cast list.

I think you can merge the two names.

Names merged.

Pre-merge acting credits for Cheung Jan (1):
The Dawn (1968)
I'm Madly in Love (1968)
Black Bull and White Snake (1969)
Purple Darts (1969)
Love Debt (1969)
Hate Me Not (1970)
The Ill Wind (1970) ... Xin Hua
Young Flying Hero (1970)
Kau Sam Neang (1970)
The Merciful Sword (1971)
Magnificent Chivalry (1971)
Fearless Fighters (1971)
Deadly Fists Kung Fu (1974)
Fantasies Behind the Pearly Curtain (1975)
Iron Swallow (1980)