With the explosion of SPAM mail and the proliferation of viral marketing campaigns, the factors affecting the rapid transmission of messages becomes more and more important. This research study focused on the impact of source characteristics and of providing consumers with additional motivations to act in propagating viral word-of-mouth. Ihe influence of strong ties and demographic and perceptual homophily are discussed in their role in encouraging people to view websites, forward e-mail messages, and try out new products. To complement these source characteristics, the presence of motivations to act such as offering discounts, providing entertainment value, and having a link to online communities was also explored. Это и многое другое вы найдете в книге Viral Word-of-mouth and Email campaigns (Sara Lim)