On the development of differential geometry in Estonia
On the expansion of the power of any polynomial 1+x+x^2+x^3+x^4+etc
On the formation of continued fractions
On the history of the isomorphism problem of dynamical systems with special regard to von Neumann's contribution
On the infinity of infinities of orders of the infinitely large and infinitely small
On the information-theoretic approach to Gödel's incompleteness theorem
On the intelligibility of the universe and the notions of simplicity, complexity and irreducibility
On the mathematical structure of Tonal Harmony
On the origin of the Korteweg-de Vries equation
On the partition of numbers into parts of a given type and number
On the Peirce's "balancing reasons rule" failure in his "large bag of beans" example
On the remarkable properties of the pentagonal numbers
On the section of a cone
On the so-called Boy or Girl Paradox
On the subjective perception of the probability of an event
On the sum of the series formed from the prime numbers where the prime numbers of the form $4n-1$ have a positive sign and those of the form $4n+1$ a negative sign
On the sums of series of reciprocals
On the values of integrals with the variable taken from $x=0$ to $x=\infty$
On what Ontology Is and not-Is
On Wittgenstein's philosophy of mathematics