Asymptotic formulas for probabilities of large deviations of ladder heights

Asymptotic formulas for large-deviation probabilities of a ladder height in a random walk generated by a sequence of sums of i.i.d. random variables are deduced. Two cases are considered:
a) the distribution $F(x)$ of summands is normal with a zero mean.
b) $F(x)$ belongs to the domain of the normal attraction of a stable law with the exponent $0 <\alpha< 1.$
The method of Laplace transforms is applied in proofs.