| | +--> 1b
  | | ---> 2c
  | | | |--> FID
  | | | |--> LAB
  | | `--> 4d
  +--> Fizika
  | | |--> 2B
  | | |--> 3C
  | | |--> 3D
  | | `--> 4D
  ---> TZK