Jay Alan Sekulow, Counsel to President Donald J. Trump, Washington, D.C., and Pat A. Cipollone, Counsel to the President, The White House, have issued an Answer to the Articles of Impeachment from President Donald J. Trump. The response, dated January 18, 2020, can be read, here:
https://www.whitehouse.gov/wp-content/uploads/2020/01/Answer-of-President-Donald-J.-Trump.pdf