Tanenbaum, A. S., & Van Steen, M. (2007). Distributed Systems: Principles and Paradigms. Pearson Prentice Hall.

Lamport, L. (1978). Time, clocks, and the ordering of events in a distributed system. Communications of the ACM, 21(7), 558-565.

Mills, D. L. (1991). Internet time synchronization: The network time protocol. IEEE Transactions on communications, 39(10), 1482-1493.

[Physical and Logical Clocks | Dilum Bandara] (https://www.slideshare.net/DilumBandara/physical-and-logical-clocks)

[Time and Clocks | Florida International University] (https://users.cs.fiu.edu/~cpoellab/teaching/cse40463/slides2.pdf)

[Distributed Systems 3.2: Clock synchronisation | Martin Kleppmann] (https://www.youtube.com/watch?v=mAyW-4LeXZo)

[A Guide To NTP Clocks and Networked Time Displays | Time Tools Ltd] (https://timetoolsltd.com/network-clocks/a-guide-to-ntp-clocks-and-networked-time-displays/)

[Clock Synchronization: Physical Clocks | Paul Krzyzanowski] (https://people.cs.rutgers.edu/~pxk/rutgers/notes/content/09-clock-synchronization-slides-6up.pdf)

[GPS and Relativity] (http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html)

[Forward Kinematics of PUMA 560 and Experiment 2 | Prof. C S Kumar] (https://github.com/virtual-labs/exp-forward-kinematics-iitkgp)

[Measurement of Capacitance by Schering Bridge | Prof. A.K Deb] (https://github.com/virtual-labs/exp-schering-bridge-iitkgp)

[Built-in Functions (Python Programming Lab) | Dr. Aparna Dixit] (https://github.com/virtual-labs/exp-built-in-functions-iitk)

[A diagram showing the relationships between the various levels of NTP servers. The blue numbers are the stratum numbers; yellow arrows show a direct connection, such as RS-232, while red arrows show a network connection. | Benjamin D. Esham (bdesham)] (https://en.wikipedia.org/wiki/Network_Time_Protocol#/media/File:Network_Time_Protocol_servers_and_clients.svg)

[Round-trip delay time δ | Maxiantor] (https://en.wikipedia.org/wiki/Network_Time_Protocol#/media/File:NTP-Algorithm.svg)

[What is NTP? Network Time Protocol Overview - study-ccna.com] (https://study-ccna.com/ntp-network-time-protocol/)