1. Multiple Fourier Series and Fourier Integrals;Alimov,1992
2. Decay of Fourier transforms and summability of eigenfunction expansions;Brandolini;Ann. Scuola Norm. Sup. Pisa Cl. Sci.,2000
3. Partial Differential Equations;Evans,1997
4. Measure Theory and Fine Properties of Functions;Evans,1992
5. The Saddle-Point Method;Fedoryuk,1977