Algebraic logarithmic singular point

An isolated singular point $ z _ {0} $ of an analytic function $ f(z) $ such that in a neighbourhood of it the function $ f(z) $ may be represented as the sum of a finite number of terms of the form

$$ ( z - z _ {0} ) ^ {-s} [ \mathop{\rm ln} ( z - z _ {0} ) ] ^ {k} g (z) , $$

where $ s $ is a complex number, $ k $ is a non-negative integer, and $ g(z) $ is a regular analytic function at the point $ z _ {0} $ with $ g ( z _ {0} ) \neq 0 $.

References

[1]	L. Bieberbach, "Analytische Fortsetzung" , Springer (1955) pp. Sect. 3