When importing references into software like EndNote or RefWorks you might find special characters and diacritical marks are stripped out.
1) Copy and past the character in.
2) If you using a Windows computer with a number pad you can hold down the ALT key and type in a numerical code for the character you want e.g. ALT 130 will insert é.
There is a list of Alt Codes available at http://www.alt-codes.net/
Penn State University has an excellent guide to typing in accents and special characters in Windows or Macs. Including Alt codes, Mac codes and how to use the character map/viewer.
These tips can also be applied in other software and web interfaces, as well as in bibliographic software. ☺ = ALT 1