There are several differences in the spelling of country names between the UNICEF files and the ISO_LU standard--although UNICEF uses the standard ISO Alpha 3 codes.
There are three fields in the UNICEF_LU file:
ISOCountryLC: The lower case spelling of the ISO country name--includes the complete list of ISO countries
UNICEFCountry: Includes the names of all the countries included in the UNICEF files..
ISOA3: The ISO Alpha3 country code for all of the ISO listed countries.
A sample of the first few entries in the UNICEFB_LU table is shown below:
The UNICEF_LU file in .xls format can be downloaded here.