you could use these levers: http://www.sjscycles.co.uk/product-Tektro-Tektro-RL520-Aero-V-Brake-Levers--Black-14956.htm and put them on the underside of the bullhorns, like
I really want an airnimal, if only they weren't so expensive...
@deleted started
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you could use these levers:
http://www.sjscycles.co.uk/product-Tektro-Tektro-RL520-Aero-V-Brake-Levers--Black-14956.htm
and put them on the underside of the bullhorns, like
I really want an airnimal, if only they weren't so expensive...