Reference gives the results in terms of so-called L functions, which can be written as one-dimensional integral representations involving products of log and dilog functions, while gives the results in terms of multiple polylogarithms.
Next-to-next-to-leading order ${\cal O}(\alpha_s^4)$ results for heavy quark pair production in quark--antiquark collisions: The one-loop squared contributions
Figure 1: Dilog graphic with the simulated values of the critical level and the ﬁtted function for k=2.
Significance tests for comparing digital gene expression profiles
Figure 2: Dilog graphic with the simulated values of the critical level and the ﬁtted functions for k=5.
Significance tests for comparing digital gene expression profiles
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