<Li> 7 Year Bitch </Li> <Li> Alice in Chains </Li> <Ul> <Li> The Gits </Li> <Li> Green River </Li> <Li> Love Battery </Li> <Li> Mad Season </Li> <Li> Melvins </Li> <Li> Mother Love Bone </Li> <Li> Mudhoney </Li> <Li> Nirvana </Li> <Li> Pearl Jam </Li> <Li> Screaming Trees </Li> <Li> Soundgarden </Li> <Li> Tad </Li> <Li> Temple of the Dog </Li> <Li> Willard </Li> </Ul> <Li> Mother Love Bone </Li>

Where did the term plugging away come from