HAMT

Hash Trie - Immutable data structure - for use in ObjC

Resources https://github.com/chaelim/HAMT/blob/master/Src/HashTrie.h

http://www.altdevblogaday.com/2011/03/22/ideal-hash-tries-an-implementation-in-c/

http://pastebin.com/DbJZmz8R

http://infoscience.epfl.ch/record/166908/files/ctries-techreport.pdf

https://github.com/clojure/clojure/blob/master/src/jvm/clojure/lang/PersistentHashMap.java

A Short History of the B-Tree

[Stratified B-trees and versioning dictionaries] (http://arxiv.org/abs/1103.4282)

RMTrees - Bagwell

RRB Trees - js

Adaptive Radix Tree in C

Optimizing Hash-Array Mapped Tries for Fast and Lean Immutable JVM Collections

Leveling Clojurs Hash Maps