EDIT

    public static Team NewInstance(Person... members) {

        Team team = new Team();

        for (Person member : members){

            team.addTeamMember(member);

        }

        return team;

    }

//************************ CONSTRUCTOR *******************************/

import eu.etaxonomy.cdm.strategy.cache.agent.TeamDefaultCacheStrategy;

    /**

     * See https://dev.e-taxonomy.eu/redmine/issues/8881

     */

        TeamOrPersonBase<?> author = book.getAuthorship();

        String result;

        if (author == null){

            result = "";

        }else if(author.isInstanceOf(Person.class)){

            Person person = CdmBase.deproxy(author, Person.class);

            result = getInRefPerson(person);

        }else{

            Team team = CdmBase.deproxy(author, Team.class);

            if (team.isProtectedNomenclaturalTitleCache()){

                //not yet finally discussed may change in future

                result = team.getNomenclaturalTitle();

            }else if (team.isProtectedTitleCache()){

                //not yet finally discussed may change in future

                result = team.getTitleCache();

            }else if (team.getTeamMembers().isEmpty()){

                //not yet finally discussed may change in future

                result = team.getTitleCache();

            }else{

                result = "";

                int size = team.getTeamMembers().size();

                for (Person person : team.getTeamMembers()){

                    int index = team.getTeamMembers().lastIndexOf(person);

                    String sep = (team.isHasMoreMembers() || index != size - 1) ?

                            TeamDefaultCacheStrategy.STD_TEAM_CONCATINATION : TeamDefaultCacheStrategy.FINAL_TEAM_CONCATINATION;

                    result = CdmUtils.concat(sep, result, getInRefPerson(person));

                }

                if (team.isHasMoreMembers()){

                    result += TeamDefaultCacheStrategy.ET_AL_TEAM_CONCATINATION_FULL + "al.";

                }

            }

        }

        result = Nz(result);

    private String getInRefPerson(Person person) {

        String result;

        if (isNotBlank(person.getFamilyName())){

            result = person.getFamilyName();

        }else if (isNotBlank(person.getNomenclaturalTitle())){

            result = person.getNomenclaturalTitle();  //TODO discuss if nomTitle is really better here then titleCache

        }else{

            result = person.getTitleCache();  //maybe remove everything behind a ","

        }

        return result;

    }

import eu.etaxonomy.cdm.strategy.cache.agent.TeamDefaultCacheStrategy;

    //https://dev.e-taxonomy.eu/redmine/issues/8881

    @Test

    public void testInRefAuthor(){

        Person person1 = Person.NewInstance("Inauth.", "Inauthor", "A.B.", "Ala Bala");

        Person person2 = Person.NewInstance("Twoauth.", "Twoauthor", "C.", "Cla");

        Person person3 = Person.NewTitledInstance("Threeauth.");

        Team team = Team.NewInstance(person1, person2, person3);

        IBook book1 = ReferenceFactory.newBook();

        book1.setAbbrevTitle("Acta Inst. Bot. Acad. Sci. URSS");

        book1.setVolume("Fasc. 11");

        book1.setDatePublished(TimePeriodParser.parseStringVerbatim("1955"));

        bookSection1.setTitle("My chapter");

        bookSection1.setInBook(book1);

        book1.setDatePublished(VerbatimTimePeriod.NewVerbatimInstance(1956));

        book1.setAuthorship(person1);

        Assert.assertEquals("Unexpected nomencl. reference", "in Inauthor, Acta Inst. Bot. Acad. Sci. URSS Fasc. 11: 248. 1956", bookSection1.getNomenclaturalCitation("248"));

        book1.setAuthorship(team);

        Assert.assertEquals("Unexpected nomencl. reference", "in Inauthor, Twoauthor & Threeauth., Acta Inst. Bot. Acad. Sci. URSS Fasc. 11: 248. 1956", bookSection1.getNomenclaturalCitation("248"));

        team.setHasMoreMembers(true);

        Assert.assertEquals("Unexpected nomencl. reference", "in Inauthor, Twoauthor, Threeauth. & al., Acta Inst. Bot. Acad. Sci. URSS Fasc. 11: 248. 1956", bookSection1.getNomenclaturalCitation("248"));

        book1.setAuthorship(Team.NewInstance(person1));

        Assert.assertEquals("Unexpected nomencl. reference", "in Inauthor, Acta Inst. Bot. Acad. Sci. URSS Fasc. 11: 248. 1956", bookSection1.getNomenclaturalCitation("248"));

        //for the following the behavior is not yet finally discussed, may change in future

        book1.setAuthorship(team);

        team.setTitleCache("Teamcache", true);

        Assert.assertEquals("Unexpected nomencl. reference", "in Teamcache, Acta Inst. Bot. Acad. Sci. URSS Fasc. 11: 248. 1956", bookSection1.getNomenclaturalCitation("248"));

        team.setTitleCache("Teamc.", true);

        Assert.assertEquals("Unexpected nomencl. reference", "in Teamc., Acta Inst. Bot. Acad. Sci. URSS Fasc. 11: 248. 1956", bookSection1.getNomenclaturalCitation("248"));

        book1.setAuthorship(Team.NewInstance());

        Assert.assertEquals("Unexpected nomencl. reference", "in "+TeamDefaultCacheStrategy.EMPTY_TEAM+", Acta Inst. Bot. Acad. Sci. URSS Fasc. 11: 248. 1956", bookSection1.getNomenclaturalCitation("248"));

    }