1. A popular ( Fourier ) integral representation for it, introduced by George Baker is 2. He discussed the recurrence relations to motivate and to obtain a convenient integral representation . 3. For every function, every point and every multiindex, the following integral representation formula holds 4. Moreover, the following Stieltjes integral representation for " T " can be proved: 5. These forms of linear combination satisfy numerous simple-looking properties, like asymptotic formulae or integral representations . 6. The Hankel functions admit the following integral representations for Re ( " x " ) > 0: 7. Where we made use of the integral representation of ? and the formula about | z s | above. 8. The one may be converted to the other by making use of the integral representation of the Gamma function: 9. They arise in the description of near-field Fresnel diffraction phenomena and are defined through the following integral representations : 10. Hopf s collaboration with Sommerfeld on integral representations of Bessel Functions resulted in the publication of a paper in 1911.