00570nam a22001577a 4500008004500000020001800045082001600063100002700079245010700106250001200213260003800225300001500263650003900278650004700317650004800364230615b    2021       ||||| |||| 00| 0 eng d  a9780707747132  a623.8 bUKH  aUK Hydrographic Office  aAdmiralty List of Radio signals : Global Maritime Distress and Safety System (GMDSS)  NP285 - volume 5  a2nd ed.  aUKb UK Hydrographic Officec2021  axii, 492p.  aPurpose of Admiralty Radio signals  aGlobal Maritime Distress And Safety System  aCommunications Systems For Use in The GMDSS