Found the original paper outside of the paywall: https://iuuk.mff.cuni.cz/~koucky/papers/catalytic.pdf https://iuuk.mff.cuni.cz/~koucky/papers/catalytic.pdf T

Found the original paper outside of the paywall: https://iuuk.mff.cuni.cz/~koucky/papers/catalytic.pdf https://iuuk.mff.cuni.cz/~koucky/papers/catalytic.pdf The ~koucky/papers/ root is also a goldmine of papers, including another catalytic one.