Publication of results totally or partially obtained using the program PDFgetX2 should state that PDFgetX2 was used and contain the following reference:
X. QIU, J. W. THOMPSON, AND S. J. L. BILLINGE (2004) "PDFgetX2: A GUI driven program to obtain the pair distribution function from X-ray powder diffraction data" , (submitted to J. Appl. Cryst.)