Related Rule
Australia
Practice Relating to Rule 13. Area Bombardment
Australia’s Commanders’ Guide (1994) states: “Indiscriminate attacks [include] those which … employ any methods or means which treat, as a single military object, a number of clearly separated military objectives in an area where there is a concentration of civilians”. 
Australia, Law of Armed Conflict, Commanders’ Guide, Australian Defence Force Publication, Operations Series, ADFP 37 Supplement 1 – Interim Edition, 7 March 1994, § 956(d).
Australia’s Defence Force Manual (1994) states:
An example of an indiscriminate attack would be to bomb a city, town, village or area as though it were a single military objective when it contains a number of separate and distinct military objectives mixed in with a similar concentration of civilians and civilian objects. 
Australia, Manual on Law of Armed Conflict, Australian Defence Force Publication, Operations Series, ADFP 37 – Interim Edition, 1994, § 502(b)(3).
Australia’s LOAC Manual (2006) states:
An example of an indiscriminate attack would be to bomb a city, town, village or area as though it were a single military objective when it contains a number of separate and distinct military objectives mixed in with a similar concentration of civilians and civilian objects. 
Australia, The Manual of the Law of Armed Conflict, Australian Defence Doctrine Publication 06.4, Australian Defence Headquarters, 11 May 2006, § 5.2.
The LOAC Manual (2006) replaces both the Defence Force Manual (1994) and the Commanders’ Guide (1994).