src/main/java/com/conveyal/gtfs/validator/service/GeoUtils.java
@Deprecated
  public static int getUTMZoneForLongitude(double lon) {

    if (lon < -180 || lon > 180)
      throw new IllegalArgumentException(
          "Coordinates not within UTM zone limits");

    int lonZone = (int) ((lon + 180) / 6);

    if (lonZone == 60)
      lonZone--;
    return lonZone + 1;
  }
@Deprecated
  public static int getUTMZoneForLongitude(double lon) {

    if (lon < -180 || lon > 180)
      throw new IllegalArgumentException(
          "Coordinates not within UTM zone limits");

    int lonZone = (int) ((lon + 180) / 6);

    if (lonZone == 60)
      lonZone--;
    return lonZone + 1;
  }
/*
Taken from OneBusAway's UTMLibrary class