“As paint I use lightfast printing ink, usually pure, but also mixed. Mixing is not difficult at all, it but can happen in very different ways. Secret means are not applied, but I can not work on them, except in solitude (at sunshine). No one works in this way. I believe that no one else can obtain the same color effects, except after a lot of practice and experience. Sometimes one print goes up to 50 times under the printing-press. [I make] Never more than one piece per day.”