Rec.	Title	Date of deletion
G.681	Functional characteristics of interoffice and long-haul line systems using optical amplifiers, including optical multiplexing	31 January 2002
G.958	Digital line systems based on the synchronous digital hierarchy for use on optical fibre cables	31 January 2002
G.167	Acoustic echo controllers	16 February 2004

Supplement	Title	Date of deletion
G Suppl. 6 (12/1972)	Example showing how the total value of line noise specified for the hypothetical reference circuit on open-wire lines might be broken down into its various components	9 February 2001 (SG 15, Geneva)
G Suppl. 9 (12/1972)	Roll effect in coaxial pair systems	9 February 2001 (SG 15, Geneva)
G Suppl. 13 (10/1976)	Noise at the terminals of the battery supply	10 May 2002 (SG 15, Geneva)
G Suppl. 18 (10/1984)	Information on submarine cables used in deep water	9 February 2001 (SG 15, Geneva)