This book, "Modernizing the Japanese Garden" by Christian Tschumi, is about Mirei Shigemori & various gardens, described as avant-gard, that he designed. It looks as though it would be very interesting reading.
I think the picture in the link below is of one of Mirei Shigemori's designs. There's also a link to a site where his grandson, Chisao Shigemori, mentions various gardens that his grandfather created.
Are you referring to "Modernizing the Japanese Garden" (which is about Shigemori's gardens) by Christian Tschumi, or about "The Modern Japanese Garden" which is about Shunmyo Masuno's gardens?
I thought Tschumi's book wasn't worth buying, but I did buy the latter - though speaking of Shunmyo Masuno, I'm not happy with what he did to Professor Mori's Tea Garden in the Nitobe Memorial Garden - at least I think if it was he who changed it.
The Shigemori book is pretty bad. Or maybe it is more accurate to say that Shigemori's GARDENS look bad. "Sterile" and "false-looking" are not qualities that I normally enjoy when I visit Japanese gardens.