Lewis, W. Arthur.
The Principles of Economic Planning / - Eighth Impression 19 / - London W.C.1 : George Allen & Unwin Ltd.. - p.128 :
Economics
X:75 / J2;2
The Principles of Economic Planning / - Eighth Impression 19 / - London W.C.1 : George Allen & Unwin Ltd.. - p.128 :
Economics
X:75 / J2;2