The probability distributions of field differences ∆x(τ)=x(t+τ)-x(t). where the variable x(t) may denote any solar wind scalar field or vector field component at time t. have been calculated from time series of Helios data obtained in 1976 at heliocentric distances near 0. 3 AU. https://www.indiamapdigital.com/product-category/books/