"powell, l s. "
Aguide to the use of visual aids: / I.S. Powell - 1 ed. - uk : british association . - ", 36p.; 24 cm."
371. 335 pow
Aguide to the use of visual aids: / I.S. Powell - 1 ed. - uk : british association . - ", 36p.; 24 cm."
371. 335 pow