This series is written from published material and its byline claims method rather than credentials, so the sources are listed. They are given as books and categories of material rather than as page citations; where a claim in the text is contested, the text says so at the point of the claim.
This volume has two problems the others did not, and both should be stated before the list.
The first is language. This is an English-language account of three musics whose deepest documentation exists in Spanish, Korean and Nigerian sources. The Korean press has covered its own industry, including its labour practices and its contract reform, in vastly more depth than any foreign publication. The Puerto Rican and wider Latin American press has covered reggaeton’s suppression, its politics and its internal arguments for thirty years. Nigerian journalism has documented the market economy, the ringback-tone business and the industry’s rebuild in detail. This book has been assembled substantially from what is available in English, which is exactly the filter it spends a chapter complaining about, and readers who can read those languages should go to those sources instead of this one.
The second is that the machine is undocumented. The recommendation and playlist systems in Movement Two are proprietary, and the companies publish selectively. Every chapter in that movement marks the boundary between what is documented, what is measured from outside, and what is inference. Where this book says a thing is inferred, it means it.
On reggaeton’s origins. The Panamanian and Puerto Rican prehistory is documented in a growing academic literature, Reggaeton, the collection edited by Raquel Z. Rivera, Wayne Marshall and Deborah Pacini Hernandez, is the standard English-language scholarly starting point, and Wayne Marshall’s writing on the dembow rhythm’s transmission is the most careful account of how the pattern travelled. The 1995 seizures and the political campaigns of the 1990s and 2000s are documented in contemporary Puerto Rican reporting.
On the Korean industry. The founding events of 1992 and the agencies’ development are extensively documented. The 2009 Korea Fair Trade Commission action and the standard contract that followed are matters of public regulatory record. The major agencies are listed companies whose financial statements and disclosures are published, and this book has preferred those filings to press estimates wherever a figure was needed.
On Nigerian music and the Lagos economy. The collapse of the multinational recording business, the role of the Alaba market, the radio-led rebuild and the caller-ringback-tone economy are documented in Nigerian business and music journalism and in academic work on West African media distribution. The coinage of the English umbrella term and the artists’ objections to it are on the record in interviews.
On the technical description of the machine. The published work of the streaming services’ own engineers and research teams on collaborative filtering, content-based audio analysis and text-based similarity is the basis for the chapter on the recommendation system. What those publications do not cover (current weightings, personalisation behaviour, any role of commercial arrangements in ranking) is not covered here either, and is marked as unknown rather than guessed.
On the royalty model. The pro-rata mechanism, the platform share and the territorial revenue pools are described in the services’ own published explanations of how payments are calculated, and in the rights-holder disclosures that follow from them. The user-centric alternative and the trials of it are documented by the companies that ran them. No per-stream rate appears in this book as a fact, because no such rate exists.
On the dembow litigation. The proceedings commenced in 2021 in the United States are public court filings. They have been repeatedly amended and narrowed, and at the time of writing had not reached a final resolution on the merits. Nothing in this book should be read as a statement about the outcome, and readers should check the current position rather than rely on this account.
On chart methodology. The incorporation of streaming into the American and British charts, and the rules governing it, are published by the chart compilers.
On the records. Release dates, personnel, labels and chart positions are from the releases themselves and from the standard chart archives. Streaming and view figures reported by platforms or labels are treated as claims, and the text says so where one is used.
On individuals. Where this book reports what a named living person has said or done, it is from public statements, interviews or documented events, and it is attributed in the sentence. Where a matter is contested (a deal’s terms, a departure from a company, an artist’s account of their own contract) the text says so.
Where figures are disputed, the text says so rather than choosing. Those disagreements are not gaps in the record. They are the record.
