Beltran, D. G. (1963). A method of determining economical sample size for sample surveys.
芝加哥风格引文Beltran, Diosdado G. A Method of Determining Economical Sample Size for Sample Surveys. 1963.
MLA引文Beltran, Diosdado G. A Method of Determining Economical Sample Size for Sample Surveys. 1963.
警告：这些引文格式不一定是100％准确.