Currently, I want to make comparison between small specimen (350mm x 100mm x 25mm thick) and standard size of prism for flexural strength. Three point (for small prism) and four point (normal prism) bending test was used as. Based from the preliminary result, the small specimen gives higher results than the standard size specimens. I also want to relate other factors that influence the results. Is there any standard (bs standard or etc), reference or anything that could help me to investigate those matters?