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The explicit expression for the electric combination of gluon GPDs H g ( E ) through the corresponding forward like functions reads: 

<img src='content_image/341645.jpg'>

Note, that the second term in (28) is the pure D -term contribution. The result for the magnetic combination of gluon GPDs H g ( M ) can be obtained in the similar way applying the differential operator ( 1 − x ∂ ∂x − ξ ∂ ∂ξ ) : ν 

<img src='content_image/341646.jpg'>

The functions H g ( E, M ) ( ν $^{)}$( x, ξ, t ) which appear in (28) and (29) defined for − ξ ≤ x ≤ 1 are given by the following integral transformations: 

<img src='content_image/341647.jpg'>

with $^{P}$− $_{n}$( χ ) ≡ $^{P$_{n}$}$− $_{1}$( χ ). Here, as usual, x$_{s}$ = 2 x − ξs (1 s $^{2}$) $_{y}$; s$_{i}$ , ( i = 1 , ... 4) stand for the four roots of the equation 2 x$_{s}$ − x 2 s − ξ 2 = 0 (see (A12) for the definitions) and y$_{0}$ is defined in (A14). The integrals in (30) are well convergent for the set of the forward like functions with the following small- y behavior G$_{2}$$_{ν}$ ( y ) ∼ 1 y 2 ν + α with α < 2. 

