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 # X-RayCalc 2
 
-X-Ray Calc 2 is a revised and improvement version of software for computer simulation of X-ray reflectivity, including normal incidence and grazing incidence X-ray reflectometry (NIXR and GIXR). Find more information about the previous version here https://linkinghub.elsevier.com/retrieve/pii/S2352711019303681
+X-Ray Calc 2 is a revised and improved version of software for computer simulation of X-ray reflectivity, including normal incidence and grazing incidence X-ray reflectometry (NIXR and GIXR). Find more information about the previous version here https://linkinghub.elsevier.com/retrieve/pii/S2352711019303681
 
 In this version, the automatic optimization based on modified LFPSO algorithm was implemented (see https://ieeexplore.ieee.org/document/10066334/ for further details).