Provided that for the purposes of this paragraph of this Article, the credit'
to be allowed for Norwegian communal income tax shall not exceeded one-half of
the said communal income tax.
 (2) Where United Kingdom tax is payable, whether directly or by deduction,
In respect of income from sources,within the United Kingdom, and that income
is chargeable also to Ncz-rvegian tax, the Norwegian tax payable by the person
entitled to such income on his total income chargeable to Norwegian tax shall
be reduced by an amount which bears the same proportion to that 'Norwegian
tax as the income from sources within the United Kingdom bears to the said
total income. Provided that the Norwegian Ministry of Finance and Customs
may decide that the deduction shall not' exceed the amount of the United
Kingdom 'tax.
 Where such income is an ordinary dividend paid by a company resident in
the United Kingdom, the deduction, in the event that it is restricted to the
amount of the United Kingdom tax, shall take into account (in addition to the
United Kingdom tax appropriate to the dividend) the United Kingdom profits
tax payable by the company in respect of its profits; and, where it is a dividend
paid on participating preference shares and representing both a dividend at
a fixed rate to which the shares are entitled and an additional participation in
profits, the profits tax so payable by the company shall likewise be taken into
account in so far as the dividend exceeds that fixed rate.
 (3) Where income is derived from sources outside both the United Kingdom
and Norway by a person who is resident in the United Kingdom for the purposes
of United Kingdom tax and also resident in Norway for the purposes of Norwegian
tax, the income may be taxed in both countries (subject to any Convention
which may exist between. either of the Contracting Parties and the territory
or territories from which the income is derived). A credit shall be allowed
in accordance with paragraph (1) of this Article against any United Kingdom
tax payable in respect of that income, equal to that proportion of the United
Kingdom tax or Norwegian tax whichever is the less, which such person's income
from sources within the United Kingdom bears to the sum of his income from
sources within the United Kingdom and his income from sources within Norway;
and a deduction shall be allowed in accordance with paragraph (2) of this
Article against any Norwegian tax payable in respect of that income equal to
that proportion of the United Kingdom tax or the Norwegian tax, whichever
is the less, which such person's income from sources within Norway bears to the
sum of his income from sources within the United Kingdom and his income from
sources within Norway.
 (4) For the purposes of this Article, profits or remuneration for personal
(including professional) services performed in one of the territories shall be
deemed to be income from sources within that territory, except that the remun-
eration of a director of a company shall be deemed to be income from sources
within the territory in which the company s resident, and the services of an
individual whose services are wholly or mainly performed in ships or aircraft
operated by a resident of one of the territories shall be deemed to be performed
in that territory.
 ARTICLE XVII.
 (1) The taxation authorities of the Contracting Parties shall exchange such
information (being information which is at their disposal under their respective
taxation laws in the normal course of administration.) as is necessary for carrying
out the provisions of the present Convention or for the prevention of fraud