Reference sources and scholarly books can provide a good overview of a topic. Look for literature review chapters and/or bibliographies that can point you to other books and articles that specifically address your research question.
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How Social Movements Matter
by
Marco Giugni; Doug Mcadam; Charles Tilly
New Social Movements: From Ideology to Identity
by
Enrique Larana (Editor); Hank Johnston (Editor); Joseph Gusfield (Editor)
Cultural changes over the past two decades have led to a proliferation of new social movements in Europe and the United States. New social movements such as ecology, peace, ethnicity, New Age philosophies, alternative medicine, and gender and sexual identity are among those that are emerging to challenge traditional categories in social movement theory. Synthesizing classic and modern perspectives the contributors help to redefine the field of social movements and advance an understanding of them through cross-cultural research, comparison with older movements, and an examination of the dimensions of identity individual, collective, and melding of the two. "