deletions | additions       diff --git a/textbf_References_https_en_wikipedia__.tex b/textbf_References_https_en_wikipedia__.tex  index 77cb51c..ecdd48f 100644  --- a/textbf_References_https_en_wikipedia__.tex  +++ b/textbf_References_https_en_wikipedia__.tex 
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https://en.wikipedia.org/wiki/Rule_of_product \\  http://www.cut-the-knot.org/arithmetic/combinatorics/BasicRules.shtml\\  http://www.cs.cornell.edu/courses/cs280/2004fa/280wk6_x4.pdf\\  https://www.youtube.com/watch?v=sEul6TMYDY0\\  Benjamin, Arthur T. Discrete Mathematics. Chantilly: Great Courses, 2009. Print.\\