Sheppard, D., & Harrison, C. (1980). Readability of road safety publications. Transport and Road Research Laboratory, Road User Characteristics Division.
Lua i Stíl Chicago (17ú heag.)Sheppard, D., agus Colin Harrison. Readability of Road Safety Publications. Crowthorne, Eng: Transport and Road Research Laboratory, Road User Characteristics Division, 1980.
Lua MLA (9ú heag.)Sheppard, D., agus Colin Harrison. Readability of Road Safety Publications. Transport and Road Research Laboratory, Road User Characteristics Division, 1980.
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