COMPUTER SYSTEMS RESEARCH
Elements of Technical Writing
2005-2006

  • Omit the period at the end of a parenthetical expression within a sentence; retain it if the entire parenthetical expression stands alone as a sentence.
    1. In technical writing, sentences often end with an expression within parenthesis. Punctuate the enclosed material in the usual way but omit the final period in the parenthetical expression.
      Punctuate the sentence outside the parentheses exactly as if the parenthetical expression were not there. 
        Incorrect                               Correct
  The growth rate has increased      The growth rate has increased
  by 12 percent each year (see       by 12 percent each year (see
  Fig. 8.).                          Fig. 8).
    2. The rule also applies to parenthetical expressions that appear in the middle of a sentence, unless it is a question mark or exclamation point: 
        If is extremely unlikely that two people (barring identical twins) share precisely
  the same gene combinations.

  At the science fair, the chemist (or was he more of an alchemist?) turned
  red wine into milk before our eyes.
  
          bacon, eggs, and juice
      Major reference works on English recommend using the serial comma. 
        The four most abundant elements in the earth's crust are oxygen,
  silicon, aluminum, and iron.
    3. If the entire parenthetical expression is a complete sentence in itself, and not contained within another sentence, the period at the end of the sentence goes inside the parenthesis. 
        (We will discuss software below.)