00729cam a22002171 4500 e 14002061 DLC 20260227111202.0 850304s1914 nyu 000 0 eng e 14002061 (OCoLC)11760643 DLC AU DLC HF5381 .A85 Ayres, Leonard Porter, 1879-1946. Constant and variable occupations and their bearing on problems of vocational education. New York City, Division of Education, Russell Sage Foundation [1914] 11 p. 23 cm. [Russell Sage Foundation, New York. Division of Education. Pamphlets] E136 Vocational guidance. Occupations. 19747 19747