https://www.geeksforgeeks.org/dsa/introduction-of-b-tree-2/
 github.com/tsoding/sv/blob/master/sv.h
 https://github.com/semitrivial/csv_parser

 Introduction to Algorithms, Fourth Edition
 ISBN-10 : 026204630X
 ISBN-13  : 978-0262046305

 chapter 18: B-Trees


 https://github.com/tidwall/btree.c/blob/master/btree.c