docs: public final CatalogGs findSubcatalogGsByIdInTc(
      final TradingCatalog pCatalog, final Long pId) {
      for (TradingCatalog cat : pCatalog.getSubcatalogs()) {
        if (cat.getCatalog().getItsId().equals(pId)) {
          return cat.getCatalog();
        }
        for (TradingCatalog cati : cat.getSubcatalogs()) {
          if (cati.getCatalog().getItsId().equals(pId)) {
            return cati.getCatalog();
          }
          //recursion:
          CatalogGs cgs = findSubcatalogGsByIdInTc(cati, pId);
          if (cgs != null) {
            return cgs;
          }
        }
      }
      return null;
    }