How to calculate a subnet mask from hosts and subnets | TechTarget
The Sky Networks - CIDR CIDR (Classless Inter-Domain Routing) notation rather than the common subnet mask 255.x.x.x when configuring addresses and networks. Refer to the CIDR Subnet Table to find the CIDR
VLSM Design
networking - How exactly is a subnet mask used when determining where to send a packet to? - Super User
CIDR Subnet Mask Cheat Sheet | NetworkProGuide
Subnetting and Subnet Masks Explained
VLSM Subnetting Examples and Calculation Explained