wilmott.com

Hi all,

I have this paper (attached) by Andreas Weber and Uwe Wystup which gives closed form formulae for Barrier options (Sec 1.2). What I absolutely can't make any decision over is the part that whether the barrier style is American or European.
I feel the formulae are for pricing the European style Barrier options. Can someone clarify?

Thanks!

American: barrier provisions are triggered by any hit prior to option's expiration.

old and good (or perhaps just old?)

Closed Form Valuation Of American Barrier Options

if not access, a pre-print version here, mostly the same, even if published version is better