Punctuation centuries meant that a standard system of punctuation was urgently required." The introduction of a standard system of punctuation has also been attributed to the Venetian printers Aldus Manutius and his grandson. They have been credited with popularizing the practice of ending sentences with the colon or full stop, inventing the semicolon, making occasional use of parentheses and creating the modern comma by lowering the virgule. By 1566, Aldus Manutius the Younger was able to state that the main object of punctuation was the clarification of syntax. By the 19th century, punctuation in the western world had evolved "to classify
The Chicago Manual of Style an interposed comma. If the author's name is used in the text, only the date of publication need be cited parenthetically (with or without the page number). In-text citations are usually placed just inside a mark of punctuation. An exception to this rule is for block quotations, where the citation is placed outside the punctuation. The full citation for the source is then included in a references section at the end of the material. As publication dates are prominent in this style, the reference entry places the publication date "following" the author(s) name. Using notes and bibliography style, the sourced