Source 1
Name of source:  Giddings, F. H. (1890). PRINCIPLES OF ECONOMICS. By Alfred Marshall, Professor of Political Economy in the University of Cambridge. MacMillan & Co., London and New York, 1890. Vol. I, pp. xxviii, 754. The ANNALS of the American Academy of Political and Social Science, 1(2), 332–337. https://doi.org/10.1177/000271629000100217
Main idea: Ten principles of economics are introduced.It answers three questions: how people make decisions, how people trade, and, finally, how the economy as a whole works.This article mainly analyzes the world view of economists from the perspectives of supply and demand, firm behavior and consumer choice theory, long-term economic growth and short-term economic fluctuations, and macroeconmic policies.
How this source links to my topic: Economics is concerned with the production, distribution and consumption of goods and serving the needs of customers. As a beginner of economics, we should not only   know what economics is, but also know the basic principles of economics. This book is very useful for those who are going to study economics. According to the information collected, we should not only study this book, but also  related articles on Western economics, classical political  economy and international economics.

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