PUBLIC LAW 90-498, Approved September 17, 1968, 90th Congress

Resolved by the Senate and House of Representatives of the United States of America in Congress assembled, that the President is hereby authorized and requested to issue annually a proclamation designating the week including September 15 and 16 as "National Hispanic Heritage Week" and calling upon the people of the United States, especially the educational community, to observe such week with appropriate ceremonies and activities.

PROCLAMATION 4310, September 4, 1974 -- Partial text

(Public Papers of the Presidents of the United States, Gerald R. Ford, 1974, U.S. Government printing office)

Now, THEREFORE, I GERALD R. FORD, President of the United States of America, do hereby proclaim the week beginning September 10, 1974, and ending September 16, 1974, as National Hispanic Heritage Week. I call upon all the people of the United States, especially the education community and those organizations concerned with the protection of human rights, to observe that week with appropriate ceremonies and activities.

PUBLIC LAW 100-402, Approved August 17, 1988, 100th Congress

Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled,

Section 1. AUTHORIZE THE DESIGNATION OF THE NATIONAL HISPANIC HERITAGE MONTH. The joint resolution entitled "Joint resolution authorizing the President to proclaim annually the week including September 15 and 16 as 'National Hispanic Heritage Week"' . approved September 17, 1968 (36 U.S.C. 169f) is amended -- by striking "week including September 15 and 16" and inserting "31-day period beginning September 15 and ending on October 15";   by striking "Week" and inserting "Month"; and   by striking "week" and inserting "month".

Section 2. EFFECTIVE DATE. The amendments made by section 1 shall take effect on January 1 of the first year beginning after the date of the enactment of this Act.

PROCLAMATION 5859, September 13, 1988--Partial text

(Public Papers of the Presidents of the United States, Ronald Reagan, 1988-89,- II, U.S. Government Printing Office)

Now, Therefore, I RONALD REAGAN, President of the United States of America, do hereby proclaim the week beginning September 11, 1988, as National Hispanic Heritage Week. I call upon the people of the United States to observe this week with appropriate ceremonies and activities.

This information taken from:
http://latino.sscnet.ucla.edu/heritage/hhhispan.htm