\[\operatorname{Hi}\left(z\right)=\operatorname{Bi}\left(z\right)\int_{-\infty}^%
{z}\operatorname{Ai}\left(t\right)\,\mathrm{d}t-\operatorname{Ai}\left(z\right%
)\int_{-\infty}^{z}\operatorname{Bi}\left(t\right)\,\mathrm{d}t.\]