Lahiri (1952) [7] suggests the Circular Systematic Sampling (CSS) which consists of taking a random number from 1 to N and selecting the unit corresponding to this random start and every k unit thereafter in a cyclical manner until a sample of n units is obtained, k being the nearest integer to Nn, i.e. If r is a random number selected from 1 to N, the sample consists of the units corresponding to the number.