On February 4th, 1949, Science Magazine published Hubbert's
1948 Speech to the AAAS Conference PDF 251 KB (courtesy of HubbertPeak.com).

Hubbert was swamped with mail, universally favorable after the speech was published but it was hardly noticed by the petroleum industry even though it was little different from the later, 1956 version which caused an uproar. Hubbert could be more specific in his 1956 analysis because of additional data and he predicted US crude production would peak in 10-15 years. This conclusion was almost universally considered outrageous at the time.