Ow and why did the visionary architectural drawings of tienne-Louis Boulee and Claude Nicolas Ledoux challenge the classical style of their time?

Pay attention to the following:
Use footnotes where appropriate ie. for quotations and ideas which are obviously not your own. These may appear at the end of the essay or at the foot of the page.
eg. 1. R.Jenkyns, Westminster Abbey, 2004, p.77.
The number before the footnote refers to a corresponding number in your text which should be placed in brackets immediately after the passage which you are referencing.
At the end of the essay include a bibliography of the books and articles which you have used, including those to which you refer in the footnotes. Arrange it alphabetically by author:
for books: Muthesius, S., The High Victorian Movement in Architecture, 1972;
for essays in a book of essays: Evans, R., Figures, Doors and Passages, in
Translations from Drawing to Building and other Essays, 1997, pp.55-91.
for periodicals: Whyatt, A., Thames Gateway London in the Millennium,
Rising East, vol 1, issue 1, 1997, pp.36-58;
for websites: W.Lawrence (1996) Greek Architecture, Pelican
Robin Osborne (1998), Archaic and Classical Greek Art, Oxford University Press
John Summerson (1986) The Classical Language of Architecture.

Hans Belting (2011) Florence & Baghdad, Harvard
Nikolaus Pevsner (1976) Building Types, T & H
Paul Oliver (2007) Dwellings: The Vernacular House Worldwide, Phaidon
Trevor Garnham Architecture re-assembled