====== TTP12-019 Massless two-loop self-energy diagram: Historical review ====== This class of diagrams has numerous applications. Many interesting results have been obtained for it. |**A.G.Grozin** | |** Int.J.Mod.Phys. A27 1230018 2012 ** | | {{preprints:2012:ttp12-019.pdf|PDF}} {{preprints:2012:ttp12-019.ps|PostScript}} [[http://arxiv.org/abs/1206.2572|arXiv]] | | |