To view the contents, you will need an archive manager like WinRAR, 7-Zip, or a specialized unpacker if the file is part of a complex installation script.
Because "537.rar" is a generic naming convention used by various creators, you should exercise caution before opening such a file from an unknown source: 537.rar
If you are looking for a of a software or a particular historical record , could you share the website where you found the file or describe what you expect it to contain? Full text of "Zoological record" - Internet Archive To view the contents, you will need an