Counting Books -- See Counting Here are entered works on counting, including counting books. Works on the theory and systems of numbering are entered under Numeration. Works on the psychology of numeration are entered under Number concept.
Counting Devices Digital -- See Digital counters Here are entered works on mechanical, electromechanical or electronic discrete-state counting devices operating on any given number base, consisting of any combination of sensing, accumulating and readout elements, and being used as components in meters, automata and control systems. Works on manual or other counters for arithmetic processes are entered under the specific name, e.g. Abacus, or under the subject, Mathematical instruments. Works on devices which detect and measure radiation are entered under Nuclear counters or the specific name, e.g. Scintillation counters.
--subdivisions Methods (Country) and Studies and exercises (Country) under names of musical instruments
Country City Migration -- See Rural-urban migration Here are entered works on population shifts from a rural to an urban environment. Works on population shifts from an urban to a rural environment are entered under Urban-rural migration.