Woke up muzzy. Cramped. Barbora’s father came at 10:00 so we had to get out of bed. He put up some lopsided shelves in ridiculous places. Drilling. Went to an exhibition at the library. New Czech Art and Architecture. A few good pieces – JAROSLAV RÓNA1 – Versmírny Pes (Space Dog)2. VIKTOR PIVOVAROV3, IVAN KAFKA4.
Jaroslav Róna (born 27 April 1957 in Prague-Letná) is a Czech-Jewish sculptor, painter, actor, educator, and writer.
I still think this of Róna’s is great. Not so sure about Róna’s later sculptures. They become quite ingratiating-public-art.

A work from 1988 — ‘Leaving Bundles in the Sky’ — is what I’ve been able to find by Pivovarov. This is almost certainly not what young-Toby sees.
Here’s Pivovarov’s wikipedia entry —
Viktor Dmitrievich Pivovarov (born 1937) is a Russian artist who lives in Prague since 1982. He represented Soviet Nonconformist Art and was one of the leading artists of the Moscow Conceptualist artistic movement of the 1970s, along with Ilya Kabakov, Erik Bulatov, and Irina Nakhova. His work reflected the complete ideologization of the Soviet lifestyle, often simultaneously expressing criticism and nostalgia for this lifestyle. Nakhova relates that Pivovarov was a major influence and first inspired her to paint.
Pivovarov was also a prolific illustrator of children’s books, with over 50 books to his credit.
In English, pivovar translates as brewery.
Ivan Kafka (born 1952, Praha) —
Kafka is known especially for his great land-art installations, in which he puts a basically utilitarian object in new relations to events in nature (for example his long-term project entitled Space of Freedom (and Gloom) – modified compositions of windsocks in different parts of Europe. However, he is also interested in investigating the possibilities of enclosed, architecturally firmly determined spaces (for example his interior arrangements of table-tennis balls, halberds, arrows, pinwheels or clock hands which move around but do not show the time, or his recent installation of a suspended, exactly defined plane of pieces of white cotton wool which is an artificial evocation of a cloudy sky).
From Hana Rousová (artlist.cz).
Not sure what young-Toby sees by him, but this is good.