According to Cantor (Mathematische Annalen 21:545—586, 1883; Cantor's letter to Dedekind, 1899) a set is any multitude which can be thought of as one ("jedes Viele, welches sich als Eines denken läßt" ...

Classical management theory was introduced in the late 19th century. It became widespread in the first half of the 20th century, as organizations tried to address issues of industrial management, ...

Effective descriptive set theory refines classical descriptive set theory by emphasising computability and algorithmic aspects in the study of definable sets and functions, particularly within Polish ...