Limited Dependent Variable Simultaneous Equation Models

[moroche]

Is there any sample program on the estima website that estimates a Limited Dependent Variable Simultaneous Equation Model?
e.g.
y1 = b1*y2 + X*A + error
y2 = b2*y1 + Z*B + error
where
y1 and y2 are endogenous
X and Z are vectors of exogenous variables
A and B are vectors of parameters
b1 an and b2 are parameters
and y2 is a truncated below at zero.
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