@inbook {Stevens1981, title = {The search for invariant acoustic correlates of phonetic features}, booktitle = {Perspectives on the study of speech}, year = {1981}, publisher = {Erlbaum}, organization = {Erlbaum}, address = {Hillsdale, {NJ}}, keywords = {acoustic analysis, phonetics, phonology, акустичен анализ, фонетика, фонология}, author = {Stevens, Kenneth N. and Blumstein, Sheila E.}, editor = {Eimas, Peter D. and Miller, Joanne L.} }