WinLLTM
WinLLTM is a Windows (Windows 95 or higher) program for analyzing dichotomously scored item responses using the Linear Logistic Test Model (LLTM). The program works with complete data only.
More information and technical details in Bechger, T.M, Verstralen, H.H.F., & Verhelst, N.D. (2002). Equivalent LLTMs. Psychometrika, 67, 120-134.