Give the edition of the text actually being cited. If there has been only one edition of the text or if referring to an old edition that happens to be the first, omit reference to the edition number. Do not write “1st ed”.

Eg FAR Bennion Statutory Interpretation (Butterworths, London, 1984).

Indicate the edition number by giving it in numerals followed by “st”, “nd”, “rd” or “th” as appropriate (not in superscript), a space and then “ed” (short for edition).

The edition number is followed by a comma.

Eg Diggory Bailey and Luke Norbury Bennion on Statutory Interpretation (7th ed, LexisNexis, London, 2017).