On algebraic structure of pre-operad
Kluge, Liivi
2002
https://www.ester.ee/record=b1688674*est
On Lagrange formalism for Lie theory and operadic harmonic oscillator in low dimensions = Lagrange'i formalismist Lie teooriale ja harmooniline operaadostsillaator madalates dimensioonides
Virkepu, Jüri
2009
https://www.ester.ee/record=b2540604*est