Unique continuation for Schrodinger operators with unbounded potentials

We consider unique continuation theorems for solution of inequalities $\text{¦Δu(x)¦ ? W(x) ¦u(x)¦}$ with W allowed to be unbounded. We obtain two kinds of results. One allows W ? L^p_loc($\text{R}$ⁿ) with $\text{p ? n ? 2}\text{for}\text{n > 5, p >}\text{1}\text{3}\text{(2n ? 1)}\text{for}\text{n ? 5}$. The other requires fW² to be ?Δ-form bounded for all f ? C₀^∞.