2006 Irisbus CityClass 491E.12.27 CNG
(https://www.imcdb.org/vehicle_1443904-Irisbus.html)
(https://www.imcdb.org/vehicle_1444138-2006.html)
(https://www.imcdb.org/vehicle_1442974.html)
(https://www.imcdb.org/vehicle_1443025.html)
2007
(https://www.imcdb.org/vehicle_1381991-Irisbus-CityClass-491E1227-CNG.html)
(https://www.imcdb.org/vehicle_1578388-Irisbus-CityClass-491E1227-CNG.html)

1995 Mercedes-Benz OF with Marcopolo Torino body
(https://www.imcdb.org/vehicle_466457.html)

Urviabus G2 - Mercedes-Benz
(https://www.imcdb.org/vehicle_1609126.html)

2005 Volvo B7L with Ayats Bravo City bodywork
(https://www.imcdb.org/vehicle_1605838.html)
2008 Volvo B9TL on Ayats Bravo City bodywork
(https://www.imcdb.org/vehicle_1047511.html)

Gillig Phantom
(https://www.imcdb.org/vehicle_633041.html)

1993
(https://www.imcdb.org/vehicle_2091973-Jelcz-120-MM-1.html)
Jelcz T120
(https://www.imcdb.org/vehicle_2091971-Jelcz.html)

2015 on Volvo B5LH chassis
(https://www.imcdb.org/vehicle_2091887-Alexander-Dennis-Enviro400-MMC.html)

2010 NABI Metro 45C CNG [453.33]
(https://www.imcdb.org/vehicle_1056354.html)

2005-07 Jelcz M081MB3 on Mercedes-Benz Vario chass
(https://www.imcdb.org/vehicle_2091663-Autosan.html)

Not an bus, but an fire engine:
Dennis RS
(https://www.imcdb.org/vehicle_2091839-Dennis.html)